it sort of depends on the context of the situation. in a tournament game silence is expected, but with just friends people will usually talk throughout the game. theres not really anything for online so it sorta jsut depends on the person.
with that being said you can just disable chat if you find it distracting.
I just played a game against someone who sent a request to chat which I clicked on because I thought it was to offer a draw as the game was a draw at that point but it went like this:
Opponent: No time bro
Me: What do you mean?
Opponent: 3 minutes left
At this stage of the game I had 3 minutes compared to their 7 minutes in a 10|0 rapid game but I've won plenty of games with seconds to spare so I wasn't bothered by the clock. It seemed like they were deliberately trying to put me off and they succeeded. As a snooker player where silence is key I dislike chat that is unnecessary and it seems like they initiated chat to throw me off. I've blocked them and disabled chat (again) but is this type of behaviour allowed? Is it part of chess and should I be more thick skinned and focussed?
It seems like a very underhanded tactic to swing the game in to their favour. Send a message which I read on my time and is designed to antagonise and affect my concentration. Very annoying.