In my opinion that's only partially true. Back in 2016 I sided with the camp that felt you stick with the hot hand. Romo already had an extensive injury history before 2016 and I remember being frustrated by Jerry's unwillingness to draft potential replacements. Some may say that was Dak, but I feel Dak was only a camp body who wasn't brought in as an expected replacement for Romo. Dak ended up having a good rookie season, but don't forget he was aided tremendously by the outstanding play at RB by Elliott. A stud RB having an MVP season will always help the QB look better.
Where Jerry played a part in Romo being replaced - Romo was the starter and had earned that spot. With that being said, when he was healthy enough to return he should have been allowed to move back into the QB1 spot. In my opinion, it was Jerry who blocked that move. Garrett was a massive puppet who followed Jerry's orders, so all signs point to Jerry being the culprit who ended Romo's career, with a bit of assistance from mother nature, of course.
I think I'm the one who said Jerry won't do it, and I still feel that way. Look at who Jerry has brought in at QB over the past 10 years, has a single one of the screamed "OMG! This guy could replace Dak"? None of them have. It's classic Jerry, and Jerry has been doing this since half way through Romo's career. Jerry simply doesn't want any competition at QB - at least not until he's forced into a corner by something like a broken back.