The mesorah makes a lot of sense to me. There are people that I know are truly pious, wholesome and sincere who testified the same about their teachers and parents. I have enough to go on from knowing the likes of Rabbis Gettinger, Fendel, Wehl (rebbi in HANC) Wahrman (rebbi in HANC), Eisemann, Tzuriel to know that they truly and without any schemes or agenda hold 100% by this stuff. Their holding by it is clear evidence that their forbears held by it. They speak of their teachers as having been on a higher and more intense madrega. These teachers include the likes of the Chazon Ish, R Aharon Kotler, Rabbi Soloveitchik, Rav Kook and the Ponovezher Rav.
Now you don't have to believe that these teachers were "perfect" to believe that they were great human beings and noble bearers of the mesorah. As an aside, no matter what taanos one has against R Soloveitchik's hashkafos, it is hard not to derive chizuk in emuna from him (in a way that I cannot from the heimishers) By that I mean, here is a man who had nothing at all do to with all the phoney baloney heimishe shtick of today (or yesterday) and yet, there was nothing in his life that drove him the way limud hatorah did (I witnessed this personally). why?? he wasn't after a rich father in law from boro park. he also didn't have to make his living with this stuff. nor vos, he actually believed in this stuff!. He is also known to have been of impeccable ethical standards and quite a baal chesed. Why?? He actually believed in this stuff. For me this is huge, pointing to the fact that this yiddishkeit thing was very real for him. Ki hem chayenu!
These people believed in this stuff with such a reality. While we have no way of measuring the sincerity level of goyish religious leaders, it is hard to find a consistent pattern or mesorah of non jewish or non frum leaders with a record of tzidkus such as we find by our own. I have no doubt in my mind of the purity of spirit of R' Chatzfkel Levenshtein, the Chofetz Chaim, R Elchonon Wassermann, or the Satmar Rav. I am in awe and esteem, of the way they lived their lives, of their purity, their holiness and their sincerity. All this is based on a combination of stuff I have heard and read (many sources, cross checked and verified). Tiny example: Rabbi Sholom Gold knew the Satmar Rav and told me incredible things about his tzidkus . This is "mesiach lefi tumo" as lauding the SR does not serve R Gold's agenda at all. Similarly, the non frum yiddish author Chaim Grade wrote amazing stuff about the depth of mind and sensitivity of spirit the Chazon Ish. I have such an emunas chachomim in these men and everything they represented. I learned shoulder to shoulder with yungerleit in the Mir with nothing at all driving them other than yedias toras hashem. (of course there were also a cast of characters who passed their days smoking and going in and out of the beis medrash with nonsense. but so what? the r'ayah is not from them!) In the same beis medrash sat R Chaim Shmuelevitz's sons (great "guys") and R' Beinish Finkel (RCS's brother in law). R Beinish Z"TL was a tzadik nistar, who, it was found out after his petirah, did amazing chasodim for poshuteh yiden. These guys are the real thing. And they all were in awe and esteem of R Chaim Shmulevitz, who in turn was in esteem of R' Leizer Yudel Finkel, son of the Alter (rebbe of e.g. Rabbi Ruderman, whom I felt I could tell was the real thing). He was also a mekurav of Rav Kook and the Gerer Rebbe in Yerushalayim, and was the father of much of the litvishe derech in mussar and hashkafa. To me, this network of shleimim is so incredibly tight and impenetrable. Also, the beliefs, traditions and attitudes are so deep and tightly held from a group so diverse that it is clear they come from a place many generations back that in turn must have been very pious and intense.
The point of all of the above is that there is a world of frum, pious, amazing yiden out there who are holding fast to the mesorah in a very real way. These people are not morons. They are a fair mix including highly intelligent people who live this thing in a real and beautiful way. I believe that we lose out by not really seeing this in our own lives. We live in a world where yiddishkeit has much more to do with how fancy the bar mitzvah is, how big the brim is, etc. Most of even the positive stuff we see, compared to what I described above, is highly watered down. We are exposed to organizational "leaders" whose role in yiddishkeit is mostly around operational policy, not actual leading by example; i.e. practicing the stuff itself in a way that can be a model for us. In Mir yeshiva, there was no such thing as rebbeim finding reasons to run all over the place doing stuff "more important" than learning. They learned all day because they actually believed in it and couldn't imagine doing anything else. This is a very simple model of leadership. (it is hard to make a case for the more convoluted, more prevalent model we find). I have no doubt that Isaac Stern has a passion for violin. He shows us his passion by playing.
There is a real world of real people who practice this stuff for real. I saw it in my grandfather, in my teachers it existed in our leaders, and it still is alive and well among sincere bnei torah and (what is probably a most underrated group) the vast "middle class" of sincere regular yiden. This beautiful world of beautiful values held by pure people who try their best, and sometimes fail but often don't, is something I yearn to connect to. The value system itself attracts me, and its being based on a long tradition of pure souls who practiced it, makes it all the more compelling.
I don't think this is about sentimentality and nostalgia. Sure there are sentimental feeling about stuff you love. Baseball fans have nostalgia about old games. But they only value these nostalgic feeling because of the underlying love they actually have for the game. The case I tried to make above is about the innate beauty of our values, much in the same way that a passion for art can be justified because of its innate beauty.