ICYMI ... the 'Million Dollar Listing' star posted a video reviewing the most cringe moments from season 5 of 'Sunset' -- and based on his snarky commentary, it's clear Josh doesn't think too highly of the hit Netflix reality show.

If his words weren't clear enough, his caption was ... "If you’d like to watch a real estate show with licensed agents, make sure to watch last nights episode of MDLLA on @peacock. If you want to watch actors pretend to be agents, tune into my newest YT video (Link in bio) where I review Selling Sunset. @estatemediala."

None of the agents currently on 'Sunset' have said anything just yet, but 2 former ones -- Christine Quinn and Maya Vander -- did, and they seem to agree.

Vander says she definitely had her license when she was on the show, while Quinn doesn't say one way or the other. However, she's squarely on Josh's side about the real focus of 'Sunset.' She responded, "The joke is on y'all if you think Selling Sunset was ever about Realestate."

CQ later clarified who on the show has licenses, from what she knows -- she name-dropped Maya, Davina Potratz and Chelsea Lazkani, and added she wasn't sure about the extras.

Now, we got Oppenheim himself to chime in on this too ... and he downplayed the apparent animosity between Josh's show and his own, telling us they're really good friends and that this was nothing but some light ribbing that's not meant to be taken seriously.

He also definitively said that all of his agents have their licenses and that everyone knows that. To be frank, we're not so sure Josh agrees. If he does, he's doing a great acting job in his attack on Jason's show.

Like we said, none of the current cast members have directly responded to Josh's insinuation some of them aren't licensed agents.