That's not entirely fair. It is disingenuous to characterize Warren Buffett's methodology as "buy and hold." Berkshire Hathaway takes far more active participation in the companies it's long on than any individual retail investor could hope to imitate (or even fathom, logistically speaking). It's not just a matter of being long on a company and buying the stock - the amount of capital they invest provides Buffett et al with involvement and corporate direction that few other institutions can command, let alone individuals.
I agree with your point that buy and hold can be a valid strategy, I just don't think that example is fair and Buffett it basically a meme in these threads now.
I think you may have misinterpreted the OP's point about sophistication - I don't think he was trying to be condescending to those with comparatively little to trade with. His actual point is valid - if you are optimizing for commissions first and foremost, you're probably doing something wrong (as an active trader). Robinhood is a platform that, by design and mission, differentiates itself on the lack of commissions, not on superlative features or strategy availability. This means that if you choose Robinhood as your platform for trading (as opposed to, say, Interactive Brokers), you're likely optimizing on commission/fee avoidance, because that's all they're really got to offer that's unique.
Commission and fee avoidance is great, sure, but optimize for that within the context of a larger strategy. It's very important to reduce fees because it can make an otherwise unprofitable strategy profitable, I agree! But you should really start by getting to the actual strategy first, and Robinhood's business directive might encourage potential investors to prematurely optimize on fees, when that is honestly not the thing that typically prevents people from being successful in the market. The thing that typically prevents people from doing well is the lack of real alpha.
If you do have a viable trading strategy with a good Sharpe ratio, the commissions will not stop you from being successful. Conversely (as one example), if you are using the commission-free trading as a way to explore strategies that you think are viable, but which are actually just risk-overloaded returns attributable to chance in disguise, then yes the commissions will eat you alive - but that's because you don't really have a working strategy in place.