The apps might not be available though. Many developers are simply stopping in the face of Google's invasive policies. I don't blame them. Say goodbye to useful apps like Newpipe.

I don't see anything on NewPipe's website about not continuing development?

A few apps have been showing pop-ups warning users in advance that they are not going to do the verification. Obtanium is definitely on of them. I think I saw something similar on NewPipe.

Yes, but that isn't them giving up developing the app, that is them fighting back!

If you install it or update it you will get a banner to this effect at first use.

It says they are giving up, throwing in the towel? It is my understanding it provided information about Googles plans and how it will impact users?

It says they will not comply with whatever registration is required. It does not say specifically what they will do, in part I assume because they had not been given enough specifics (for example if it remains possible to sideload but not to be in a third party app store, would they continue to develop with that diminished accessibility?). Additionally YouTube itself has been making some system changes that, outside NewPipe's control, may make it functionally impossible to use the service without being logged into a Google account, so they may be suggesting that they think the writing is on the wall for them.

I'd say some od those apps starting with N and ending with E might... but I'm saying that only because of my intuition... might be the exact reason why Google introduces this policy

Developers will also be able to publish their apps on free Android devices like Graphene, I don't think that apps like NewPipe will go away.

I remember when Microsoft got in trouble for bundling a web browser with the OS.

Sure, they have no obligation but the way you describe Newpipe to paint it as "obstructive" feels off to me.

When you offer a free service, by definition of it being free, you can't hold consumers of that service accountable for not furthering your revenue. They are impeding revenue only if it's not actually free (or only under false pretenses) which dismantles your first sentence here.

If my employer wants me to use a phone for work, they can buy whatever phone they want for me. I'm not going to buy a separate one just for them.

This is hopefully an exciting time to consider a Motorola device, since they are partnering with GrapheneOS, but I worry that Google will block Google Play Services on any device that doesn't comply, so this might actually be a demoralizing time to be a GrapheneOS fan, when we watch them worm their stupid walled garden nonsense into the Motorola version of it.

You don't need Google Play at all on GrapheneOS. You have to option of installing a sandboxed version of Google Play, but it isn't installed by default. Google's verification shenanigans are otherwise irrelevant to Graphene, it only applies to apps distributed through the Google store.

Blocking Play might not be that bad if some frameworks/efforts crop up to allow easily targeting devices without it.

The vast majority of apks work just fine without Google libraries. In some rare cases, things such as notifications that depend on Google's servers may not work if the developers haven't not implemented an alternative backend such as a direct connection.

Most of your F-Droid developers will leave the ecosystem if forced to pay Google to publish outside the Play Store.