I think everyone will have a bias towards what they grew up with and/or are accustomed to, but with baseball it's probably a legitimate argument. I mentioned before that I think basketball today is too 3 point happy, and I much preferred the 90s/00s style, but look how popular the NBA is with young people and in general. It's not impacting the sport in a negative way, it's just a difference of opinion. With baseball, I very rarely see people (young or old) saying how much better the game is today. No one is talking about the beauty of three true outcomes, or openers, or players taking notes out of their pockets to tell them where to stand/what to throw, or 4 hour games, etc. Every time the topic of baseball is brought up on a more national level it's always about "how does MLB fix the game?", or some variation of that. There is a real problem. That doesn't mean people who enjoy today's game are wrong, at the end of the day it is all subjective, but MLB is testing out an insane amount of rule changes because the people who genuinely enjoy today's product from an aesthetic standpoint are likely the minority.
If today's MLB resembled 1998-2003 (or whatever years you want to group with the "Steroid Era") when it comes to the variety of skills you were watching everyday, then the "get off my lawn" arguments would likely closer resemble what's going on in the NBA today, and not what's actually happening.