I've got an older tripod - a Britek CM101 with a fairly simple'style' of head - mostly taken out for special occations in the film and early digital camera era.
After fixing an unrelated issue - I noticed that any "modern" camera I've tried it on seems slightly loose and I ended up needing a spacer - I've added a sheet styrene spacer/clip in the image below. .
Have the screw holes on cameras gotten shallower over the years, has there been some kind of "old age" related shrinkage (happens to the best of us) or have we been using it wrong over the last few decades?
The most common reason the screw is too long is the tripod usually has a rubber pad affixed to its platform. This pad is compressible and it tends to lose its resiliency over time and thus tends to stay compressed.
The tripod attachment screw is actually a two piece design. The large black knob turns the attachment screw, while the silver "wings" just above it are a locking ring that moves independently. To attach it to your camera you screw it in just enough to engage with the bottom of the camera and then tighten it down with the silver locking ring. This is supposed to be a "quick attach" type design.
To more literally answer your question, the depth of the threaded portion on the camera isn't strictly standardized but has (on average) remained the same for the last 70 or so years.