Assuming a QB is right handed, then the LOT must be a pass blocking specialist able to handle every type of rusher from the bull rusher to the speed rusher.
The ROT of course must be a good enough pass blocker, but the QB has vision to that side of the ball and thus has a better chance of avoiding an advancing rusher from his right side.
It is true, however, that in today's game you can't just stick anybody out there at ROT. And, in the passing game a good pass blocking ROT has much to do with just how long a QB can hang on to the ball so that deeper routes can be run.
Perhaps a fair statement is that today's ROTs have to be more than glorified OGs as they more used to be. As with any position, finding someone to man ROT decently isn't that difficult. But finding the excellent ROT, like Havenstein, is much harder. Those deep and deep intermediate routes the Rams run has much to do with the prowess of both of our OTs.
Still, a really good LOT is a prized possession and it is reflected in the size of their contract as compared to any other Oline position.