Can't speak for the other countries, but the England players actually are political activists. They are heavily involved in social justice politics, have clashed with government ministers, wear clothing during matches with political messages, and make political statements on the pitch. Thats why people are angry about it. Because they are making themselves out to be hypocrites.

>Football is for everyone, but not if you are gay.

This message is now endorsed by England players. Maybe they should wear that as an armband?

They don't want to miss out on the world cup. Thats more important to them than taking a stand or having silly things like morals. In the end they will bow down and do whatever FIFA and Qatar want. If they were told to deliver an anti LGBT message or face being kicked out of the tournament they absolutely would.