I don’t think we have metrics on that, but from what I can gather, only very-low-end PCs would see much difference between C++ and Blueprint, IF there is indeed any difference at all. On most modern computers, the difference in ticktime would be so small it would pass as a small bump between frames - it wouldn’t drop the FPS.
And even should Blueprint be so tick-inefficent, it comes at a major advantage: there’s people (like me :P) who only have a very limited knowledge of C++ who get access to a very powerful, if not the most powerful game engine on the market to make games as they see fit. It gives the smaller creators - the “ideas people” - an easy to learn tool to make concepts come alive. And for that I’m very grateful.