Rock climbing pedantry warning:
I haven't done a deep dive into their social media, so there may be other evidence of rock climbing experience, but this post alone leads me to believe they are novice climbers, if that.
Rock climbers use a dizzying amount of jargon, and I don't see any of it in that post. Looking at the at the terrain, a climber with any outdoor experience would call that a scramble, not rock climbing. In a scramble, you need your hands for balance, but not to pull yourself up or lower yourself. While climbing adjacent, no experienced climber would refer to a scramble as climbing.
Also, experienced climbers know that while scrambles are less technically demanding than climbs, many climbing injuries occur during the approach, not the climb itself. Experienced climbers have a healthy respect for a scramble, and consider not only the technical difficulty of the terrain, but the consequences of falling, no matter how unlikely.
From the topo maps of that area, taking a tumble there could lead to serious injury, or even death. I'd at least want a helmet and some technical shoes before attempting it. The post references another consideration experienced climbers would consider before undertaking a scramble: who else is around? Climbers make hard things look easy, and if there are a bunch of people watching you (which there would be at Delicate Arch, they might think they can do it, too. If people follow you out, could it put you in danger? Block your return route? If so, it's probably not worth it.
TL;DR: From this post alone, I see no evidence of climbing experience. It doesn't use the language of climbing, it demonstrates a safety third ethos uncommon among experienced climbers without a death wish.