> As you can see, UTC is not a proper, continuous time stream. It has breaks in it wherever leap seconds have been added
I can not see that. 23:59:58 - 23:59:59 - 23:59:60 - 00:00:00 is perfectly continuous, proper, and even monotonic, or at least as much as 23:59:58 - 23:59:59 - 00:00:00 is.
> When you receive a package with a computer-generated time stamp, it is showing this fudged UTC number, not the actual number of seconds according to the atomic stream.
I think you are mixing up UNIX timestamps (which are their own thing) and UTC. UTC and TAI both indicate exactly same thing, there is perfect 1:1 mapping between UTC timestamps and TAI timestamps (ignoring pre-1972 era).
https://robotsinplainenglish.com/e/2022-11-20-stopwatch-time...