Is there a way to query the value of RUNTIME DESTINATION for a target after an install(TARGETS) call

Same for LIBRARY DESTINATION / ARCHIVE DESTINATION

add_executable(foo)
install(TARGETS foo RUNTIME DESTINATION my_prefix)
# .......
get_property(TARGET foo PROPERTY ????)

It seems that install commands are a separate entity from targets, and that information is in no way available after the fact?

Right. There’s nothing against having a single target installed multiple times, so simple properties don’t seem like the right solution either.