Good studio monitors are transparent. ATCs (the newer v2 with ATC tweeters) for instance IMO have a very smooth top end - even the passives like the SCM11. Not hot treble at all with decent amps. The SCM40 v2 I have for instance is very full and if anything errs ever so slightly on the warm side (to be fair to ATC this is not part of their studio pro range which is tuned slightly differently - Eg SCM19 vs SCM20 pro).
The cheaper JBL Lsr series are not hot in the treble at all either.
Even the Genelecs, while they certainly have a bit more bite in the treble with the default dip switch positions vs ATC however I still wouldn't call it hot treble. There are three aspects in my experience why people say monitors have hot treble -
1. Good quality monitors are very revealing of any faults in the recording. If you try to play bad quality files and badly mixed music you will hear the faults. That is after all their main purpose. The plus point for casual listening is anything recorded, mixed and mastered well will sound sublime. People sometimes mistake this revealing transparent nature when playing poorly recorded music. Harbeth and Spendor for instance (which I also have) are a bit warm and a lot more forgiving and mask a lot of faults but are less true to the recording. Also really well recorded stuff never scales the peaks of satisfaction a fully transparent system can. I call it photoshop for sound - Harbeth polishes up a mediocre recording and makes it more tolerable lol.
2. Most studios are very absorptive with a lot of acoustic treatment. Most studio monitors come with dip switches to adjust the treble and bass roll off. Most people don't set dip switches correctly in my experience for a reflective home space. Further most such speakers work perfectly well in regular more reflective home environments also after the room has been measured using something like REW and a suitable calibration of the speakers and room correction has been applied. In my experience many audiophiles don't know or else dont care to do this as they are used to coloring sound to their preference by changing things in their chain. In fact room correction (or at least being aware of your room modes, peaks etc) along with a bit of tasteful and minimal acoustic trestment helps equally even with any passive speaker amp etc in most home room setups, especially with bass.
3. As with passive setups, coloration (which can be pleasurable as per personal taste) can be introduced with a dac, cables and a tube preamp (and to some extent EQ) if so desired. For instance from time to time I use a NOS dac and a tube preamp with my Genelecs. It certainly is less accurate but it suits my personal taste for certain poor recordings. This also means there is still some room for tinkering lol. Most people never try this. The advantage of a transparent active speaker is it can be whatever you want based on what you put further up the chain.
Also just FYI, I have all of the above speaker brands, so all of this is from personal experience.
. I think you understood the situation well.