No only this, the main problem with mining altcoins is the small hashrate of the network, while that may give the impression of being able to mine more coins, the difficulty is subject to double at any given time, but that certainly is not the case for BTC since it takes a ton of gears to increase the hashrate by 5-10%.

another reason is the technology limits, altcoin gears still have a lot of room for improvement because they are fairly new, in my previous comment I talked about mining dash (x11) , and you can see that we went from about 1200w and 17gh on the D3 to 4400w and 540gh on the Spx36 , or in other words from 70w per gh to 8w per gh , that is about 9 times more efficient, which was good enough to send D3 to the garbage.

But if we do the same thing on BTC ASIC, old school S9 does about  80-90w per th , while the latest and most efficient gear S17pro does about 39w per th, that is only about twice as better, and we are talking about 2 years of on-going improvement to get this point.

Let alone mining your favorite altcoin with GPU and then a x100 times better ASIC is introduced and the dev team of your coin do nothing about it.