Why isn't anyone considering solo mining alts?

[Lontor]

I am just having this thought in my head about solo mining.
Why are people who are buying Bitcoin solo miners not looking into something else?

I accept that Bitcoin is king, but we have very good coins that are easier to solo mine than Bitcoin.

Litecoin, Dogecoin, Monero, Bitcoin cash.

Why isn't anyone directing their miners to solo mine them? Since solving a block on them is highly likely compared to trying to solve a block on Bitcoin.

[FP91G]

Although the probability of finding a block in the Litecoin, Dogecoin, or Bitcoin Cash networks is higher than in Bitcoin, the reward in altcoins is still very small compared to Bitcoin.

The market for solo altcoin mining hardware is virtually nonexistent, with the exception of Bitcoin Cash, which uses the same algorithm as Bitcoin.

[JeromeTash]

The other question you should be asking is why altcoin mining is not as popular as Bitcoin mining, especially after ETH stopped POW in favour of POS. For example why are we not hearing people buzz about Ethereum Classic,  Litecoin, ETHW, etc.?
The answer is pretty simple... the profits are not that exciting. So same logic can apply to solo miners