It's more accurate to say
Mimblewimble offers good privacy, but nobody uses it.
So no privacy at all.

Ln may or may not have good privacy, but because we can't  measure it it's hard to recommend.
generally custodial in which case you don't have privacy from you. 

Monero offers default good privacy guarantees out of the box with a good UX.
Just don't think you're going to swap into Monero from an exchange and swap right back out and magically have good privacy.