A Dutch colleague at my company says Europe is doomed because it can't solve the immigrant problem...

‌He is an older Dutch colleague (late 50s) whom I've become quite close with after working together for 3 years.
According to him, Europe has completely failed to respond to the immigrant/refugee issue, and it has reached a point where nothing can be done anymore.... He says there is no solution...
Personally, I revisited Belgium the year before last for the first time in about 10 years, and I was so shocked to see the city center packed with numerous women wearing niqabs/burqas that covered their entire bodies in black cloth, as well as men with the heavy, unkempt beards characteristic of that culture...
I went to a tourist plaza in front of a famous cathedral, but the surrounding restaurants were filled with Halal establishments, making the atmosphere feel so alien. It wasn't the beautiful image of Europe I saw when I visited 10 years ago at all, and it even felt a bit scary...
(Personally) I feel like one of the reasons Korea is a good place to live is that multiculturalism hasn't spread as much as it has in Europe yet...
Especially since there are still relatively few followers of those religions in Korea, it makes it a good place to live...