Now a question arises again in the mist of the bitcoin network congestion. Since Altcoins are depending on bitcoin on any necessary upward movement, does it mean that altcoins network also congesting to produce high transaction fees?
Particular altcoin's congestion does not depend on bitcoin upward moment rather on the usage of altcoin itself and to answer to that, yes if it has more users than it can handle, it'll get congested.
If you meant paying high transaction fees due to Bitcoin price increase (that causing altcoin price surge as well) then that's correct. Transaction fee you pay on particular altcoin network is based on altcoin itself rather than USD value, so if altcoin value increases in USD value then you pay more transaction fee, but this has nothing to do with congestion.
This might be confusing so here is an example: if you pay 0.0001 ether for making transaction on ethereum network at 2000 USD ethereum price then it'll be 20 cents transaction fee while for the same transaction with ethereum being valued at 4000 USD, you will pay 40 cents transaction fee.
Or the congestion is for all the cryptocurrencies?
Cryptocurrencies includes token as well but tokens are based on coins (like Aave on Ethereum, solend on Solana) — here chains can get congested on which token is deployed on but token itself can't.