in terms of something i'm shipping to users, i would much rather have to worry about the nuances of TOML than of YAML. with TOML, i don't have to worry about e.g. remote code execution because someone figured out a clever way to trick my yaml into running arbitrary code somehow. that kind of shit is annoying.

is it uglier? sure. but it's peace of mind...

in terms of config i'm using myself, say Kubernetes stuff, i really love YAML...because i know exactly what it's doing and i generally keep things simple. it's nice for that, it just does way too much IMHO...