Someone already mentioned the hoarderware issue, which is big for me, so I'll give my other concern.

Years ago on Twitter I believe it was lcamtuf that asked "Would you pipe a text file into less?" and Dan Kaminsky (RIP) replied -- "Not now that you asked if I would, no." The obvious implication is that people largely didn't think of simple text parsing utilities as places of concern for security issues, but that is not really in line with reality. I work with crypto and it seriously matters if I got owned in that I can lose amounts of money entrusted to me that I could never hope to recover or repay. I believe it is a basic fiduciary duty to use as much code as possible written in safer languages. Sublime Text is a massive C++ app and I can't look at the code. I am going to preferentially treat the Rust app as better. There's plenty of CVEs in editors. If I could I would replace every binary written in an unsafe language on every machine I ever use.

My editor touches every bit of infrastructure I have. I use it every day to change the behavior of production machines. I have no choice to treat my editor as trusted. So it needs to be trustworthy to the maximum degree possible.