Ultimately the issue is meta because if you decide not to build with microbricks and then try to host your gamemode all the little monsters are gonna come to your server and be like WTF? Where are the awesome atombrick mesh objects? This server SUCKS and the build is BAD! and then leave to go play on a server with 4 hundred trillion bricks and maximum key-jingle detail
The "just don't use it" argument has existed since the discovery of fire, but has never worked in practice. You're going to incorporate microbricks and it will make the process of building less fun
i think this counterargument is an invalid one since the whole point of disallowing microbricks is to prevent people looking to make those kinds of builds from doing so on your server, and the outcome you're hypothesizing is that exact goal being achieved. if they dont build in anything but microbricks its unlikely that they would build much without them, and if they're not unreasonable they'll be fine (but grumbly) making do with normal bricks.
and in any case there needs to be a server-set brick size restriction due to near-unbounded size bricks being allowed, so trolls cant place gigantic bricks and take up all the building space near spawn on a public block-party-esque build server, so it makes sense to also allow microbricks to be controlled via the same method.
unfortunately the devs didnt have the foresight of putting this in prior to officially supporting microbricks, so the standard has shifted, but i think the establishment of both being standard can be achieved by putting this in prior to full beta/official launch
