so would you say religion of hinduism is/ should adapt to eating beef!? or is that still a no- no based on fundamentals
There is bull sacrifice in Vedas (and also later texts) for example (though some commentators say it was more figurative and esoteric than literal)....but other instances cattle are called upon to be protected (cattle is wealth, the mother cow and her calf symbolise the godliness in all creation etc). This is key because major definition of what makes an orthodox school of thought in Hinduism (as opposed to hetereodx) is do you recognise the sanctity of Vedas as god given word (i.e do you accept it as Sruti, i.e heard from God).
So from my understanding, the decision must be left to individual...but society can make an argument to inform and persuade him of merits of either...and also enforce norms etc based on majority (for social stability).
The norms you see in force mostly come from the advent of Buddhism (which really undermined the earlier sacrifices, both animal and also fire altar...because Hindu priestly class evolved to the populist movement of Buddhism around that period)...and also solidified by the last puranic avatar (Krishna) who is cowherd.
But there is no dogma for or against at level seen with say pork in islam for example (which is expressly forbidden in a central god given tenet...or is it in Hadith? I forget....)....but rather you can say lot of "sunnah" arisen around beef taboo/cow slaughter in the 3rd/4th waves of what is Hindu culture more generally.
It all boils down to your understanding of what is Hindu religion vs Hindu culture. To me a religion is defined by a dogma....but how applicable is the core original dogma (Vedas + Upanishads) to todays Hindu evolution and norms?...it really depends. After all this is why Hindu itself has concept of kala (time) and the kaliyug (the removed, egotistic time of humankind)...i.e things get worse (entropy) the further removed from the original creation and highest period of man (when he was fresh, innocent, open slate, devoted to his creator and his creation etc) that we go.