Vast majority of investors would honestly be better off just buying BTC and maybe ETH. There are a few alts that have been through a couple market cycles that are still relevant in the space, XRP and ADA are two of them. Here is the trick with alts, just about anything will pump in a crypto bull market and it's easy to 10x+ your money. However, there is no reason to hold longer term and you should sell into the bull before the market crashes.
Here's a good example from last cycle- You could have bought ADA at under 10 cents from late 2018 through most of 2020, only to see it pump to a little over $3 fall of 2021. Let's say you had invested 5k at a price average of 5 cents, so 100,000 ADA. Your investment in 2021 would have grown to $300,000. Now, if you decided to hold it through the bear market your ADA is now worth approximately $25000.
Now, let's compare this to BTC. Let's say you invested 5k into BTC at an average price of $5,000 from 2018 through 2020, which was very realistic btw, and you have 1 BTC. Your investment would have peaked at around $69,000 in 2021 and at the absolute lowest point it would have been worth around $16,000, and more recently between $25,000-$30,000. You really haven't lost all that much by holding on an asset that will still be relevant for a while. Meanwhile, some alt you made crazy gains on may not only have crashed hard but possibly not even return to those prices again. I'm not saying ADA specifically is a bad alt, just using it as an example.