I'm glad that Google has signaled that they are going to further tighten the restrictions on background app activities in future releases. I hope they follow through with it.
I think Apple has done a better job at this balance by not letting people shoot themselves in the foot at the cost the odd useful service not being possible.
It would be a shame to have to turn off all of them. I found most of them to be useful.
Anything you can do with an app you can do as well with a website.
Any actual app, not just a website in form of an app, which did computational task, data recording, or kept services available, is impossible to create now.
Run tracking app that doesn’t require you uploading your GPS data to Google Fit? Impossible.
Messaging app that doesn’t route all your private messages through Google Cloud Messaging? Impossible.
EDIT: before downvoting, read the comment below from morsch, he and I explained there pretty well the issues.
All Google did is restrict what apps can do in the background, and announced that there will be further restrictions in the future: all background tasks will have to be done through the JobScheduler API.
This does not prevent apps from doing stuff in the background, it just prevents them from doing whatever they want, whenever they want -- they will have to follow the proper procedure.
If you don't see the app in front of you, iOS will very quickly kill it if it has any background tasks.
It's a leaky abstraction, but honestly I like the implicit promise/guarantee between the scheduler and the user.
I only get annoyed when I want some batch task like uploading photos, but even then it's not too hard to leave the phone powered on and unlocked on my desk until the photos upload...