Then that was not a good candidate from the get go? What about hiring people that really care about the product they're building and not just tool fanatics?
One good reason to avoid a job doing Hotwire is so that you can take a job doing React for a similar amount, where your experience applies better and where you'll gain more transferrable experience.
In short, it's probably better for your career to work on React.
What I don't get is why as an owner/stakeholder/CTO/lead would pick the worse tool (in some context) just because everyone is using it. Well, I do get it... I just don't agree.
If you read between the lines here, everyone is just picking React because everyone else is picking React, that's the only reason apparently. It drives me mad, but honestly I do understand it.
Also, I'm not 100% sure it's for the "same amount". To me it looks like Rails jobs have higher salaries, at least around here. But that could be because most Rails devs have many years of experience, I don't know.
In short, it's probably better for your career to work on React.