I first noticed that issue in regular gnomish Ubuntu 23.04 but unfortunately it appears the same in Budgie 23.04.
In Budgie Desktop Settings, try to set Ubuntu Condensed font for title, interface and so on.
It won’t be applied - you’ll end with a regular Ubuntu font, not the condensed one.
There may have some app’s where it’s applied ( gimp maybe because it’s older gtk ? )
Here ↑ I have added budgie-desktop as affected but maybe it’s not the best way to do ?
As far as the interface font, I can’t comment on that because I am not familiar enough with what is going on there.
However…
The same fix mentioned in the pixel saver issue also appears to fix the title bar font at least. Testing it, I can now set the title bar to the condensed/bold/etc, whereas i cannot on the default 23.04 Budgie install.
Am not an expert but I suspected something related to variable fonts.
On 22.04 ( and 22.10 ) each Ubuntu font « is » its single file whereas on 23.04, each font variant is a symlink to one of the family - variable - font :