They aren't different aspects of the printing press though. Keep in mind that I'm speaking about printing press factories as a level theme, not only as a diegetic structure. Aspects of a printing press factory both visually and gameplay feature-wise were only in Act 1. After that, you're outside in a snow-enveloped cherry blossom forest with ancient ruin architecture. Which is cool, but has almost nothing to do with printing presses besides coincidentally being outside of one. If those two acts were split up into different parts of the game instead of being consecutive, nobody would ever assume that they would fit into the same zone.
Lava Reef's acts are actually organic in being consecutive because they're both underground and you switch out the lava for pretty crystal formations (along with both acts sharing different forms of metal contraptions). They're pretty different, but I can get how they connect to the other in the same area and share an underground/cave level trope.
Another example of a zone where the two acts organically connect into each other while looking different is Stardust Speedway. They look quite different, in how the first act is full of vegetation and the second act is futuristic, but they share different eras of similarly music-themed layout to connect their trope themes (lyres in the past of Act 1 and brass instruments in the present/future of Act 2). Along with taking place on this thin racetrack thing whatever…
Going off on a random tangent, I could never really tell what exactly Stardust Speedway was supposed to be even in CD. It's this weird floating racetrack on top of a city at night and the track is made of musical instruments that are only arbitrary aesthetic that don't actually play into any gameplay mechanics in the level. When I hear "Stardust Speedway" I think of some sci-fi space level racetrack like Starlight Carnival in Sonic Colors, although I guess it refers to a racetrack with the background of a starry lit night. That's perfectly fine, but then why doesn't the zone have some sort of music term or pun to reference the instrument architecture scattered all over the place for no real apparent reason besides looking cool? I can only surmise it's going for a loose "highly populated cultures are known for their music" aspect, I guess. It gets even weirder when you notice that Metal Sonic gets fought in a music architecture-filled zone instead of a factory, but he loosely fits the racetrack aspect of the zone. The only Sonic zone that actually has gameplay features centered around music is Music Plant Zone fromonic Advance 2, and I think it's a shame that they've never done anything like that since. Music-themed locations in video games are freaking awesome.
Back on topic though, you could make Press Garden Act 2 anything loosely nature-esque like Mushroom Hill, Angel Island, or Marble Garden from S3&K and the interconnectivity/contrast between Acts would almost be the same in being two almost completely different areas squished into one two-act zone. Looking back at gameplay of the levels, the only loose connection between the two acts is how there are loose bits of cherry blossoms in the brick architecture. Which helps, I guess. It still feels random to connect a propaganda printing press factor to an oriental winter wonderland, but the developers said something about being inspired by the Meiji Restoration era of late Edo Japan, so probably there was a bunch of printed propaganda around then.
I don't blame you for not noticing anything different Studiopolis Act 2 lol. It seems to only try switching things up in having film reel platforms you can run on to spin into other places and electric wires you can roll through like the tubes in Chemical Plant. Making the bosses police and weather channel-themed were surprising yet fitting though, especially the latter.
EDIT: Wait, I just remembered that Mirage Saloon has piano keys you can bounce on. That's such a great touch for a saloon-themed level.