What do we consider doom?

Listen, I know this is a probably a very loaded question, and everything is subjective.

So what is doom? People say genres don't exist. I personally think that's bollocks, myself, but that's beside the question. I listen to some stuff that I highly doubt most people here would consider "doom" but it's pretty doomy.....or at least gloomy? We have a festival here called Colossal Weekend that kinda focusses on that "genre", ha, where I've been introduced to some bands I know I'd never normally hear, and they are sooooo good - but maybe not doom?

For example this is one band: https://youtu.be/lAqEx05ama0?si=2CSLQFk1lsoSCtLH

Edit: btw I love this sub and the love that happens here. You all are great fucking people 🫶