The diversification argument is flawed and does not apply here. Every alt you stack will eventually lose value against bitcoin. This is a fact. Just look at the price curve denominated in bitcoin.
I participated in an ICO in 2017/8 and bought 6000 XTZ with 1 btc. No matter how much the price of XTZ increased in USD, it never surpassed 1btc, but actually lost ~90% of its value in BTC!
It's the value in BTC that matters, because it's sound money, not in fiat, a currency that governments can print indefinitely. The data is clear.
I actually started stacking ADA a few months ago along with some other alts because of their staking feature. I don't like putting all eggs in one basket, but then again, I've never used real-life, everywhere-expendable money to purchase crypto so I guess I'm not that concerned if my strategy goes south. Of course, I also stack sats wherever and whenever I can.