I am a relative newcomer to Hearthstone.
While there are definitely some people who use emotes sparingly and in a respectful manner, (such as to say “well played” just before the end of the match even if they lost,) about 19/20 of the people you meet will do stuff like spam “thanks” 40 times after you make a mistake. It gets REALLY old REALLY fast.
My friend who taught me to Hearthstone recommends hitting Squelch right at the start of every match. It’s what he does. The few times I forgot to do this, I usually regretted it.
If most people already hit Squelch first thing each and every match, it would be advantageous to simply let people toggle an option and that squelches each and every game at the start of the game. There will be less toxicity in the game and we could instead concentrate fully on the cards.