Such an underwhelming response to such a glaring flaw...
Literally, if this was default behavior and the mouse modifiers were complete and worked as intended, I would have exactly
zero problems working in Reaper.
Seriously, why do MIDI items disobey timebase by default and require a tedious workaround to behave correctly? If there was an action to make all items ignore project tempo I would not complain.
It's the needless editing of individual item source properties that gets my goat. What if I disguise him as a llama?