Of course animal sacrifices were there. To evolve one has to be truthful to know where one stands and how he arrived there. To whitewash the past deeds of our ancestors and to give fanciful and creative interpretations will be self defeating.
An average Hindu today will not know the difference between a Homam (called havan in North India) and yagnam (known as yajnA in North India) though both are agni kAryams. The two fundamental differences are homam is performed sitting while yAgnam was performed standing upright and a homam does not need a "yUpA" whereas a yagnam needs it. The "yUpA" stambha is the fence or a piece of wood embedded to the earth to which the sacrificial animal was tied.
The brAhmaNam of Sukla yajurvedA (shathapAtha brAhmaNam) in fact gives the comprehensive list of animals brought for sacrifice in aSwamedhA.
You can also note that people in modern times erect a "stambhA" to the people who sacrificed themselves or became a martyr to a greater cause or for betterment of a community. It is my belief that the "stambhA" concept had its origins in "yUpA stambhA"
I would definitely not call vedAs over-rated. It contains a lot of precious and useful stuff and gives a blue print of how Hindu thought evolved over time. But the useful stuff is so scattered among the mundane and vEdAs are so vast that it would be like searching for needle in a haystack. It is impossible to study in detail unless one's life requirements are taken care of and no one is providing such a facility.
The story of Buddha dying because of consumption of poisoned mushrooms is Buddhist attempt to whitewash their history.
I do not think mushrooms was known in Indian subcontinent then, but I am not sure. It will be interesting to find out when
mushrooms became considered to be an edible stuff. Even today many conservatives do not touch mushroom.
I do not know about this story and if you can give some references it will be helpful. What I have read or learnt is that someone took
askance to some big Hindu stalwart (not sure it was Adi Sankara) in partaking of sOmA and to silence him that personality drank molten iron or nails or whatever.
Herein also lies another attempt to whitewash a bit of history. Though both sOmA and surA were intoxicants (supposedly) exemption was granted to sOmA consumption (and made it ok on special days like yagnA etc) surAbAnam came to be looked down to and over a period of time became a taboo. The increased scarcity of sOmA became the reason for distillation of surA is what I would think to be the attributed cause.
By evolutionary nature people started to give up surA and it (to be free of any intoxicant consumption) became a virtue in the subsequent texts.
