No, it is not always a good idea. If you care about your user's privacy a single bit, you should self-host. Easily done thanks to https://google-webfonts-helper.herokuapp.com/fonts
You're more than welcome to make your on effort stripping that out after the event, of course.
Heck, if I've done my job properly, you can nix all my styling and read my content as you wish, but that's your palava.
As for your battery - I'll plant a tree and say a small prayer for its sacrifice.
This because a) I'm not happy with Google tracking my users and b) I've been professionally making websites since the mid to late 90s and so started off in a world where an entire site came in at under <100kb, images included.
I'm not one to needlessly and unthinkingly throw up excess pageweight
And what if I want to use Garamond?
Your stance makes no sense beyond your own peculiar prejudice.
- ed
Again, if YOU don't like MY content the way YOU want it - then YOU make the effort to change it as to how YOU want.
Anything else is simply, well - disrespectful - as you choose to imply.
If I set up the stylesheet to have an order of preference, with a fallback to default system fonts that mangle my considered layout, then you're perfectly free to do what you will - but again (and we're going around in circles here) - it's my content, I'd rather like to display it as I wish.
Look, I'll be honest - there are times and situations where I wish there were still properly text based browsers that could read web content (assuming it's been marked up well enough in the first place) and display it in green-glowing monospaced terminal text - but there aren't. The world's moved on - I'm sorry you don't like it.