[spiderfarmer]

I know you're probably looking for English language websites, but if you just want the satisfaction of knowing that forums are still "a thing":

This is a Dutch forum for Dairy Farmers. It's at the root of a lot of innovations: https://www.prikkebord.nl

This is a Dutch forum for tractor enthusiasts. The people there are very helpful and you can basically restore a tractor as a newbie with their help: https://www.tractorfan.nl

Even though these seem like very specific niches, both websites have tens of thousands of daily visitors.

[samuell]

In Sweden we have a great and pretty vibrant forum for runners: https://jogg.se