Comment # 3 on bug 1206502 from Thorsten Kukuk

(In reply to B from comment #0)
> Normally, you'd expect that if the timer isn't run at the time (0:00 +
> randomized-delay) it will trigger at the next boot. 

No, this is not what we expect.

> However, this isn't the case at all: This behavior was changed with this
> merge in systemd https://github.com/systemd/systemd/pull/11608

Exactly for the reasons mentioned in the bug report we don't expect that, and
need and depend on the current behavior, we were really happy that this did
change.

Else transactional-update would slow down the boot process and login of the
user  massively. We had that in the past.

If you use only your computer for a short time every day, you cannot expect
that you get all daily updates reliable anyway, the time may be too short.

Your mentioned PR points to https://github.com/systemd/systemd/issues/21166
which explains in the last comment what you need to do: you need to adjust the
configuration to your use case.
We cannot let everybody else suffer just because there is one use case where
the default does not fit, in this case, you have to adjust the configuration
options.