Partial compressing the forks will not hurt anything. Not sure why anyone thinks it would. Just don't pull them down to end of travel, leave a little room for them to move. Rear bag guards on the other hand are a very bad idea, regardless of how far you've already gone, or how long you been doing it. Just not safe, you can bend them a strong kick, the only reason you haven't experienced damage is you have not had a bad incident. I pull down on front using a KIWI Indian frt bike mounted bracket (google it) and from frame forwad adjacent to rear foot peg bracket and also use a Condor mount.
The next time you tie to those rear bag guards just think "are these strong enough to hold the bike if bike/trailer were on its side"? and the answer is no, they are not. You are correct in pulling forward, but there are other factors beside just holding it upright going down the road.