Ideally websites wouldn’t specify a font at all, other than cases where that’s a necessary part of the design.
The capability is nice to have—for example, if your website is a coding tutorial website, and you have interspersed code examples and prose, put the code examples in a fixed width font. But it is over-used. For example, why do sites pick serif vs non-serif? Leave it up to my browser.
This is why I almost always send emails as plain text. I want people to be able to read their emails in any font they would like, not necessarily the font I used when I wrote the email.
This isn’t just superficial, some people might use certain fonts that are easier to read for dyslexia, and I don’t think I should make their life artificially harder if it’s trivial for me to simply send a message as plain text.
The problem with that is that we've already lost this fight and now "plain text email" means "the recipient will see it in 11pt Courier New".
As for accessibility, the people who need that have already set up the required font overrides and other stuff so it doesn't really benefit them much to use plaintext.
It's sad to think about how things could have been, but that's not the world we live in now...
I am ok with them reading it as 11pt Courier New. To me the whole point of sending messages as plain text is that it doesn’t really matter to me how they read it. If they want to be lazy and read it with the default that’s fine by me, at least I gave them an option.
Also I like using text because it shows I’m not hiding any kind of tracking images or anything like that.
On the other hand, fonts can be an expression of your personality. Shouldn't it be preferable to centrally enable overriding fonts instead of forcing every site designer not to use custom fonts to express themselves? Theoretically, it is easier to remove formatting than it is to add it. Therefore, this functionality should be part of the browser, not the website. Firefox has this as an option: "Allow pages to choose their own fonts, instead of your selections above".
Personally, I quite like the site's design and its font. My gripe often is light gray text on a darker gray background. The bad readability that so many newer sites seem to prefer makes me question my eyes or my monitor capabilities. Reader mode in Firefox is also often very helpful.
“Ideally” here is a statement of what I’d find ideal. I’m not nominating myself as font-police or suggesting that we force people to do anything.
But, the feature is overused, IMO. Anything can be used to express a bit of personality, but I do think it is sometimes specified in cases where it really isn’t.
The capability is nice to have—for example, if your website is a coding tutorial website, and you have interspersed code examples and prose, put the code examples in a fixed width font. But it is over-used. For example, why do sites pick serif vs non-serif? Leave it up to my browser.