Non starter, the only parallel is that you use the word bloat, really.
The engine classes are what’s bloated, and obviously you control what you add into the final project however you see fit.
I think we all use slush/test projects to manage testing vs final work anyway.
In a sense, you should be concerned about what you include.
On the other hand OP was asking about stuff that isn’t that easy to control.
For everyone else, there’s also this.
Using blueprint the engine will include kismet. That’s a bloat-load of functions that may actually never even get used.
I really don’t think IWYU will go as far as excluding functions that aren’t actually used from a header file - and I could be wrong, but I do doubt it because of the way stuff compiles.
Ergo, in theory, a cpp project where you directly include only stuff you need into the classes, would always have a lower profile than a blueprint one.
In practice, we can all agree that if you went and started from near 0 with every project you made you’d get nowhere really fast…