Why are footballers hugging, kissing and breathing into each other’s faces?

I think like our football or hockey, that they are in a bubble with their team, have tests every day or every other day. If one tests positive, the whole team is in quarantine.

the screen is full of these guys hugging, kissing, high-fiving and generally congratulating each other

Don't worry! The "gals" also do it here, whether it's netball, cricket, or football, but only when they've got something to celebrate which sometimes is not too often!