a couple of general points:

1) the reason the reconstructions here look like “the leftover templates of gaudy pieces of theme park shit” is because they’re reconstructions. this is not actually what these statues looked like, and in my opinion they do roman art a massive disservice. the reason they look so “gaudy” (which is actually the exact same colonial attitude that led directly to the literal whitewashing of graeco-roman art, nice, very nice) is because the colours have been applied flat, with no shading or blending to give the impression of shadow. looking at contemporary roman portraiture, it’s clear that they did actually have quite a sophisticated grasp of shading and colouring, and to imagine that they would just suddenly forget how to do the dark bits when they were painting on stone is ludicrous. for context, this is a portrait of paquius proculo, a fresco from pompeii, dating from around 20-30AD, ten years earlier than that bust of caligula:

(also of interest in this regard are the fayum mummy portraits, dating from the second century AD; again, although they are of varying quality, the best of them demonstrate a clear understanding of shading. for example:

and, to be honest: do you really think a civilisation that produced this

just, what, didn’t get paint? these reconstructions are laughable, not because they’re colourful but because they’re presenting an incredibly sophisticated culture as unable to understand simple artistic concepts; something that i think itself contributes to the idea of colourfully painted statues being ‘silly’ and ‘gaudy’, which again is an incredibly colonially-influenced idea.

2) the reason graeco-roman statues are often missing the noses is because most excavated statues are generally missing the noses. they are fragile. the head of a statue is basically a football with details; the nose is the only protruding part and is comparatively narrow and thin (as opposed to, say, an arm or leg, which takes more force to break off but is still very much detachable, c.f the venus di milo) and is very, very easy to break off. although i am absolutely the last person to deny the racism that has been present in classics, the noses thing is really not a great example.