I hope he targets something better than a vt102 (going for 520 like Zutty would be good) and remembers to do extensive checking with VTTEST. Blog post from the Zutty creator about correctness: <https://tomscii.sig7.se/2020/12/A-totally-biased-comparison-...>
(I have also been bitten by terminals calling themselves `xterm-256color` or some such thing while not being remotely xterm-compatible; GNOME being the worst offender, as usual. My daily driver is mlterm¹, which is pretty good in that respect² — its main downside for me is its idiosyncratic font configuration, which is tailored for multilingual flexibility, not the English-only programmer.)