I agree about the images, silly human vanity.
There will be no difference between using mumsnet, whatever your search engine of choice or chatgpt at the moment, as under the hood its all hosted in the same Amazon/Microsoft (or proprietary datacentres but not many left outside of large finace/pharmaceutical/research). The environmental impact there is impossible to seperate out from other traditional web hosting etc. The big impact is/will come from dedicated AI datacentres and they are largely still being built. And crucially, because they are new, they do, or will, be able to take advantage of a clean slate and will be built with much more of an energy impact mindset using water cooling, excess heat turned used for heating nearby buildings etc (this is standard in Finland for most datacentres already, for example) and will be built to more modern standards of energy efficiency, unlike the rickety old colos shoved in refurbished factories etc like the datacentre I was working in today that didnt even have proper hot/cold airflow aisles.
I dont need to be an expert at the language yet, although I am pretty proficient now in one week (once you know a few, its really just the syntax that changes, like if you can speak English, Spanish and German, picking up Italian wouldnt be as hard as starting from scratch on your first language and having to work out what's a verb, what's a tense etc first). It's more a test of how quickly you can use modern tools (like AI) to assimilate new information towards a goal, and to demonstrate commitment and interest in the product. Also most code now is edited, recycled, rejigged rather than written from scratch, at my level anyway.