It's true that our preferred coins might be having some issues that needs alts attentions but sometimes if we are not in a haste we would still have patience for a while but if it's doesn't long feel okay to wait we have coins like BNB, LTC etc that could would serves as the best option to make transactions.
From the On set, I have always valued everything because they all serve different purposes which is why it was created in the first place, now that the need has arise I guess those who don't value alts must have seen it's need now. it's always good to look at everything in both the negative and positive effect before making decisions.
What are the best coins to use at a time when there is network congestion in the main meme pool?
We can use litecoin, BNB, TRX, Matic , at least these are coins that I know have a low transaction fee.
As Dr. Has listed above here I think they are currently the best one can use for fast transactions.