I'm pretty sure for me "mining.fyi" wouldn't have created any associations with landmines (although "mines.fyi" does seem to match the contents of the website closer).
It'd be really interesting to see A/B testing results about what most people associate the word "mines" with (I wouldn't be surprised if that would be landmines in this day and age).
Even "mine.fyi" would be better at not making me think "landmine", although that would instead get read as "belonging to me".fyi.
I assume this is probably because most people don't see mines (as in gold mines) mentioned in plural very often. Or if someone does refer to multiple mines at once, they usually also specify the type of mine at the same time, like, "the cadmium mines in [country]" or similar. Or if talking about old, abandoned mines in an area, they're usually referred to as such.
The word "mines" on its own without an adjective usually does mean landmines, I think.
(I also immediately assumed this was about landmines.)