I never had any problems with hornwort other than extreme overgrowth.
It's an excellent way to get a lot of vegetative action for free in a new tank. When you grow it, you'll always have extra. So it can be useful for a new tank where you want to buffer the cycle with a lot of plants. Just drop in a few pounds of hortwort trim.
Also some small fish eat it, it can harbor algae which fish can eat, and also snails can breed in it which some fish enjoy a lot. Baby fish can hide there even with semi aggressives swimming about, a few strong ones will find safety in the floatsam. I find there is value in this plant. For the same reasons I also like floating wisteria. They have their place.
It really should be left to float - any part you bury or try to secure will just melt off. A downside is that as it spreads it will block out light to the other plants in the tank so in a planted tank I wouldn't bother. Get something more controllable, it grows insanely fast.