I teach IT for seniors (basically a class room full of your Nan asking how her phone works) and I 100% agree with both of your points.
For experienced users, a lack of distinct buttons, and the use of icons only has the potential to slow you down.
For new users, learners, and people with cognitive or visual impairment these features make websites and apps boarderline In-usable.
It’s very hard to teach people how to use a computer when I must first teach them an endless codex of icons and symbols, and train them to mouse over anything and everything in case it’s a button.
Like wise, companies like Google need to stop being cute with confirmation buttons that say “got it” or “I’m in”. Stick to basics like “okay” and “agree”, because a lot of IT students in community education are non-English speaking, so indirect buttons like this are even more confusing. And for those of us who are fluent in English, we’re often scanning a page for specific text, and we’re even less likely to recognise a button is a button if the text on it is something that has never traditionally been put on a button.