Froggie (and others):
Chassidus as originally intended by the Besht was problematic. Yes, he did introduce new ideas into Judaism. He claimed that learning Torah was not of utmost importance, and instead shifted the focus to tefillah, along with happiness. His followers did things such as turn cartwheels while davening, spoke in tongues, and other strange actions. There are other teachings which were concerning, and I won’t get into all of them. They can be summed up by his asserting the primacy of Kabbalah over traditional thought, even when it came to Halachah. Kabbalah is not supposed to be learned while young, and definitely not before one has a solid foundation in the traditional sources of Tanach, Mishnayos, and Gemara.
Chassidus ended up becoming accepted because a few generations later, the leaders walked back on some of the ideas, and accepted the traditional views, merging some chassidic thoughts into them. Most of the things that were problematic were abandoned (although not all).
So Chassidus as the Besht envisioned it is long gone. Yet as I said, some problematic parts do remain.
But let’s be clear about this: The Besht did NOT have a mesorah for his teachings. He didn’t learn about the supremacy of tefillah over learning Torah from his father (he was orphaned at the age of 5) or his Rebbe.
There are no seforim on learning from the Besht. Only quotes from his students, and mostly on matters of Chassidus. So there is absolutely zero proof that he was knowledgeable in Shas. In fact, the people who supported him had hoped he’d become a Rabbi, but he frequently skipped cheder to walk in the woods, and they gave up on him. When he finished cheder (at the age of 12), they gave him a job walking escorting the small children to cheder in the morning, and davening with them.
My personal belief is that the stories of the Besht were inflated by those who came after, such as the Maggid of Mezritch, Yaakov Yosef of Polonye, and others.
Since chassidus today was tempered by the traditional Jewish population, and they abandoned most of the teachings, chassidus became more accepted. But if the many of the practices were problematic, why do we think that those which remained are ok? If the source had problems, wouldn’t it be better to cut off all those teachings?