I myself had trouble for the longest time with getting into mythic+, people would very rarely accept me. I basically had to be the first dps to sign up as that usually gets me a pass based on my ilvl. Sometimes that would get a decline. I got together with my buddy and together we ended up building up our key progress from zero. This was about 2 weeks back.
Today we’re running 10s and 11s like its a joke, our gear went from 400 - 460. We’ve ran 50+ mythics. Still have a hard time getting into groups. Why? Because I disagree with that elitist piece of trash and turned off the stream of information from my end going out.
I think you should bring the player not the number. Hence when using LFG to find people for my groups I take the higher geared person as well as try to build a composition with the team. Don’t care about how many runs you’ve done, don’t care if you’ve only ran once in the entire expac. If you know your class and are willing to make mistakes and learn you’re welcome in my group.