Rocky Linux is no different from CentOS Linux; both have whatever the corresponding RHEL has.
The question is thus what does Red Hat guarantee about RHEL?
I don’ know.
I do know that el8.7/el9.1 updates had qt5 update from 5.15.2 to 5.15.3.
The qt5 is libraries and the *.2 → *.3 did break binary compatibility.
For all the packages in RHEL/Rocky that was no issue, because rebuilt versions were in the point update.
For third-party (e.g. KDE packages in EPEL) it did mean rebuild, rebuild!
On the other hand, I do know that some RPM’s built for el7 do install on el9 and the executables can run.
The last one is critical because it encodes the exact version used at build time. But you only get this requirement if you use the private apis declared in qt5-qtbase-private-devel. If you don’t do this the “level 2” guarantee should hold. (In other words: not every 3rd-party package needed a rebuild.)