@MT_Switch
The "all welcome" lobbies all being a lie is definitely a problem and racism should of course never be excused.
Sadly, there is actually a non-racism related issue why many Germans can't play with many players in South Afrika:
Some of the most popular German ISPs throttle their connection speed to South Afrika to such an extent, that the game becomes straight up unplayable. Nobody knows why they do it, but afaik there is nothing the customer can do directly to lift that restriction.
I, as a customer of such an ISP myself, couldn't join any lobbies with South Africans in them due to that for the longest time.
Giving the Russians the benefit of the doubt (maybe a mistake, but whatever), I'd assume that they have a similar problem.
My working solution is to just use a free VPN. It's not perfect and does increase your ping by like 50 ms. But it turns the game from "literally unplayable lag fest" to "pretty good". I'd recommend Proton VPN, but many others are available.
If you want to do a connection test with a German having such a shitty ISP, just pm me and we can hop into a test game.