Obviously I wasn't comparing Anakin's overall aptitude to Rey's, just citing another instance where a Jedi opens themselves to the force and it pretty much takes control for a bit. But nice try trying to take a single sentence entirely out of context.
As for Kylo; by that point in the fight he was badly injured, we saw earlier in the film what a bowcaster hit does to *armor*. He took a hit in the flank and is visibly bleeding and seen hitting his would just to keep himself alert. Then Finn also wounds him and Rey suddenly explodes with the force he's not ready and quickly overwhelmed. Not unlike Luke's final outburst in the throne room. And let's be clear about this, Kylo is no Darth Vader. It's implied his training wasn't completed as a Jedi and Snoak himself said he has yet to finish teaching him to be a...whatever doctrine that guy follows. Probably not Sith, but something similar.
Vader had several orders of magnitude more experience than Klyo. He's fought Sith Lords and their trained assassins and untold numbers of Jedi, at the temple and in the years after order 66.
For all we know, this is only the second time Kylo's been in a real fight with another force user. The first is presumably when he turned on Luke and even so, we don't know the details of that yet. For all we know he was smart enough to wipe them out when Luke was away and never confronted him directly.
So yeah, an unseasoned, badly wounded Kylo could be beaten by a talented but untrained force user who he deeply underestimated (and was in the process of trying to recruit.) It's really not that big of a leap.