Naturally there is huge variation in the amount of monitoring or policing we are willing to do about certain behaviours. I think if you're willing to police jumping on the couch and you place value on that item of furniture then you will be strict. I have chosen to fight different battles with my kids due to different priorities.

My kids still understand how to respect my belongings and their own when we place high value on them. They also understand house rules at other people's homes. I don't think we can make blanket statements about whether or not jumping on the couch indicates a lack of respect. Your kids respect what you respect and teach them too. I hate our couches. I kept them knowing the kids would trash them because I can't be bothered policing couch activities. Each to their own.

But the OP was asking if they should relax their rules, so it really depends on whether the rules are helping you or hindering you. Can you let it go or is it a priority for you? We are all different and it's ok to just pick your battles based on your own family experience.