Because medical technology in the 25th century is more advanced. Many more wounds and illnesses can be treated in the field or in the comfort of a crewperson's own quarters, and the recuperation time is much shorter, so far fewer beds are needed. Current day parallel: there are less than half the number of hospital beds in the US today compared to 1960. Additionally, the TNG Technical Manual species that the holodecks, cargo bays and shuttlebays can be converted into emergency wards for mass casualty situations, but not normally required, seems likely this is still the standard operating procedure on ships like the Titan-A. We saw this procedure once (TNG: Night Terrors) when Crusher was dealing with mass casualties from USS Brattain.
That’s all speculation and not mentioned in the show. And one would think that at least sickbay would be brightly lit, so the doctors could, you know, actually see what they’re doing.
The vast majority of medical procedures in the 24th and 25th century seem to involve using handheld tools that can be programmed with tactile buttons or light up screens, injecting people with hyposprays that don't need precise aim, or using the biobed (again, light up screens). Bright lighting would actually be a distraction in most of those circumstances.
One is a semi reboot of TOS, reimagining TOS for the 2020's. The other is a slavish recreation of the 1990's Voyager set.
You could also consider that the Enterprise is a front line, jack-of-all-trades, Starship. It's designed to deal with any situation it could come across, while the Titan is stated to pretty much be a dedicated science vessel. The Enterprise may very well be called into deal with intense medical situations, or deal with combat conditions where a large medical ward is required. While the Titan is never expected to deal with such a situation.
I think there was a line in the episode as well about them opening up either an auxiliary cargo bay or science lab to double as an additional medical facility cause of all the patients. The regular set is just the one story lab, while that shot is a CG build and extrapolation of a larger sized facility.
Wait until you compare the corridors aboard the RMS Titanic (launched 1912) with those on the HMS Queen Elizabeth (launched 2014)...
Can someone tell me on this Frontier day poster on the top is that Enterprise from TOS movies or Enterprise from Strange New Worlds?
That top enterprise is from TMP / TOS movies (movie Refit 1701). Edit: Ninja’d by Macintosh - Well played!
... and just about every hospital in this country is completely overwhelmed because of a lack of beds and Nurses. Emergency Rooms are swamped on a daily basis with waiting times often being days for patients to be admitted, because they have no beds available to put them in. And also because of this, the Nursing Staff are more often than not completely overwhelmed and the dropout rate for Hospital employees has become a crisis.