I believe it works with point releases but not major releases (ie not 13.x to 14.x). If you do this its best to always "reset all settings" afterwards to get the settings defaulted for the particular version you are reverting to in case there were things added or changed in the newer version. That will typically make things work smoother when you go back.Mostly that will work but not always. I have often reverted to an earlier point release using the equivalent Windows iTunes shift key with the update button or by using iMazing. However there are times when it hasn’t worked. Presumably because of a change in iOS structures. So it is worth keeping an old backup somewhere. Either on the PC or in iCloud.
Not everyone has a PC or Mac though.