Hah!

It's not even that they won't speak Dutch, often they can't! Sometimes you'll be hard-pressed to find someone capable of speaking Dutch in Amsterdam in some shops and restaurants. I've had people look sheepish/annoyed for presuming to use and expect Dutch in my own country.

Working an IT job in a company of ~30 employees, someone joined who didn't speak Dutch. They would always excuse themselves and have lunch in their office¹ because it was very obvious that half the people just didn't really interact with the previously lively conversation anymore and were just biding their time to get back to work. Those who did speak, it worked but it's not as jovial as before. Sure, these people can all hold a presentation about their field of work, or order a sandwich with the correct words in England, but a spontaneous conversation about something random? It's a different set of vocabulary that you need every day, and far from everyone has that

¹ yes, we made clear they shouldn't do that and they should feel invited and part of the team. Many people did interact. And many of us made sure they were, at least, not having lunch alone in their office. Situation unfortunately remained as it was until I left

It helps make the rest of us look good.