That sucks! As long as a device can decode the signals, I don’t see why they should phase it out just to be compatible with DAB+ (especially when infrastructural costs are not a major factor).
FM receiver on phones + 3.5mn jack was a crucial source of local radio transmissions. I suspect some phones still ship radio receivers but the popular types like Samsungs and iPhones don’t seem to care (or perhaps that competes with their music and podcast markets).
If that would be possible, how would you moderate comments, seeing how random things can get? Federating with only approved finstances (federated instance)? What if you keep your blog, then push every post you make there to your solo-community on a finstance? You can engineer your comment section on the blog to pint here or fetch the comments content from fediverse to your blog…