In my experience when I lived in Holland, compared to me my friends and colleagues from English-speaking countries had the additional problems in trying to learn Dutch that people would tend to switch to English when they heard them speak in Dutch (probably because they picked up from their accent that they were native English speakers) plus their own fallback when they had trouble expressing themselves or understanding others in Dutch was the "lowest energy" language of all - their native one.

Meanwhile me - being a native Portuguese speaker - suffered a lot less from the "Dutch people switching to English when faced with my crap Dutch language skills" early on problem (probably because from my accent they couldn't be sure that I actually spoke English and they themselves did not speak Portuguese) and my fallback language when my Dutch skills weren't sufficient was just a different foreign language.

So some of my British colleagues over there who had lived there for almost 20 years still spoke only barelly passable Dutch whilst I powered through in about 5 years from zero to the level of Dutch being maybe my second best foreign language, and it would've been faster if I didn't mostly work in English-speaking environments (the leap in progression when I actually ended up in a work environment were the working language was Dutch was amazing, though keeping up was a massive headache during the first 3 or 4 months).

That said, some other of my British colleagues did speak good Dutch, so really trying hard and persisting worked for them too (an interesting trick was when a Dutch person switched to English on you, just keeping on speaking in Dutch).