I do hate that it's forced on some sites. At least make it an option with a warning that it's not recommended to go without it.
Worse is when they don't offer text 2FA. I know it's not considered secure but it has to be better than no 2FA at all right?
I hate having to install apps just to be able to login to one specific site. I run a custom rom now so anything that's going to be in Google Play is not going to work anyway. The other issue with apps is that it's basically a black box, there is no real easy way to backup the data so that if you get a different device you can restore it not to mention the privacy aspect, most apps are also data miners. I heard if you save the QR code they give you to set it up you should be able to set it up again on a different phone, but what if their particular app does not allow that? They could make the QR code a one time use, which in a way would make more sense from a security point of view.
Imo the best approach to 2FA would be if they used some kind of open standard, and you could just use a program on a computer or browser extension etc, something easier to backup and where you have more control, and not need any specific phone OS for it to work on. I presume there probably is such standard, but most sites are not using it and use their own app.