Personally, I don't find them useless and I don't see them "ruining everything". How are we going to expect the masses to be able to use these networks if memecoins are causing them to become unusable? Memecoins are the perfect stress test for these blockchains so everyone can improve the current networks we have.
That's a good point. "Meme" coins often attract newcomers into crypto/Blockchain tech because of their inexpensiveness. I understand they're not a good long-term investment, but at least they're a great way for people to learn how crypto works. If developers improve on-chain transaction capacity, they must do it carefully to avoid sacrificing decentralization in the long run. That's where L2 networks come in. If all "meme" coins lived on L2, we could experience lower fees and faster settlement times on main Blockchain networks. Shiba introduced the "Shibarium" L2 network, while some other "meme" coins are moving to ETH-based L2s such as Base and Arbitrum.
Ultimately, the market will decide which coins stay and which go all the way down the drain in an instant. Just don't go crazy spending all of your life savings into "meme" coins, and there should be nothing to worry about.