They mentioned working on future versions of Dojo... if it was going really badly they would just abandon the project....
Dojo isn't just hardware, there is supporting software, a lot to debug and optimise...
It is a bit like batteries,,,, 4680s didn't mean Tesla would stop using competitors batteries, sometimes the competing product is the best option and the fastest path to the desired result.
Would they start the Dojo project knowing what they know now? That is the difficult question to answer... one risk is that competing product becomes high priced or hard to get.