Why bother using Tor for a transparent chain? Just use Monero. You'll transact over Tor and neither your address, nor the recipient's, nor the amount sent appears on the XMR chain
Monero is useful for breaking the chain BTC->Monero but if you for example want to deposit BCH to your memo account you need to convert to BCH first, it is at that point you use tor.
If you're going to post to memo, where the tx will be recorded in cleartext and broadcast to the world, why on Earth would you care whether someone knows your IP/BCH addresses?
That was just a example, say for example that you want to do something you don't want to tie your IP to that do accept BCH but not Monero, that is what the tor integration is for.
It will be interesting to see if privacy coins actually gets widespread use, I think that regulatory bodies will start to crack down hard if that ever happens.
There is still a need for customers to obscure the IP of converting non-private coins to private coins because private coins gets delisted from fiat on ramps.
Ideally it would be possible to buy monero directly and withdraw it, never converting it, just buy and spend. But practically more likely to withdraw some non-privacy coin and convert.