Then , i can understand what you say but i am sure MSFS can support it. As when you do boarding / unboarding you don't fly .
You don't understand it's not an fps/performance problem:
there's a known hard-coded limit in MSFS that no more of 1000 Simobjects can be present in the simulation at any given time, this limit has probably been inherited from FSX, since with that engine, you would likely have exhausted memory (FSX is a 32 bit app) way before you could create 1000 objects, so whoever decided that limit though it was enough.
MSFS has a much more efficient graphic engine and video cards today are not comparable to what was available when FSX was made and, with careful usage of LODs, it wouldn't be any problem having way more objects, if they are well optimized. However, that limit is still there and, if you reach it, first objects will disappear, then Simconnect will start to break apart, not accepting any new commands, making all add-ons stop working as they should.
That's why, until the limit is lifted, we need to be very careful and trying to comply with it.