As I have said in the past, there are plenty of good free ones, and there are also spotweb (spotnab) sites that are great as long as your a fast (ie dcma).
Also the “arrrs” were designed with usenet first, its not an afterthought.
if you want to get access to good indexers, then yeah you may need to wait until you get am invite or an invite period opens, but you have to do this, its just how they operate.
you can do torrents and usenet in your arrr, at the same time. So nothing stops you from having both.
but the SPEED AND RELEASES youll see on usenet are unsurpassed and probably at least a week earlier than on your torrent sites.
Also you can run your own indexer for usenet (wont be as good as some because it wont deal with obfuscated posts, but as a backup it will be fine)
Id suggest you go down the rabbit hole and decide for yourself if you like it, you can always cancel.
oh and usenet is encrypted (if you enable it, ie port 563) so not much chance of knowing what your are doing. No more than a VPN company letting on to what a user was doing.