No, it’s not like that at all 
The game was developed as a client-server type of setting for dedicated servers and you are buying a license for the game software itself, you aren’t buying a service to use official servers. The fact that they host some of their own if just a bonus…
That’s a bonus privilege that is NOT included in your purchase price which is why they treat them separately and don’t even bat an eye banning you if you don’t like their strict rules they simply filter you out from those servers…
They look at it as your playstyle simply not being in line with the way they want THEIR servers to function (just like any private server admin can ban you if you don’t respect their rules) and take no action against the game licence you purchased and you can continue using that on any other server or single player 
This is not ME saying this btw… they stated these on multiple occasions…
And no, it was most definitely not developed for official servers, they are just a subsection of those with very strict rules. Like I said in my first post, their only goal with official servers is that the people who have nowhere else to go to experience multiplayer have a public place to go to do that…
Imo the biggest mistake they made is naming official servers “official” instead of “public” which would be a much better descriptor and official implies that they’re supposed to be better in any way and giving people false expectations.
Oh also:
Because it’s not… buildings have actually a minimal impact on performance since they’re using instanced meshes…
Basically an entire connected building, regardless of how many pieces it’s made up of is a single object, with very minimal amount of unique data per piece (health basically)
Compared to that placeables are all individual actors… even a tiny coffee mug is a separate actor with it’s own replication and tick and everything and has a much higher performance impact than any building piece
So if you would be suggesting a placeable limit, that would actually make sense from a performance point of view.
However, from what I understood from their approach and statements, the goal here is not performance, but rather minimizing the physical size players take up so there’s more parts of the land available for others to build - being able to cram as many people as humanly possible, like I said in my first post…
The performance is just secondary, and sure if you deliberately abuse stuff like place a ton of torches in a tiny building to cause lag, you’ll get banned for that too, but the main priority is to leave as much land available for others as possible.
That being said I fully agree that they should switch to much better quality servers!