What's reasonable is if you want to avoid using Google services (for whatever reason), then you do not need to be fanatical about it. Move off gradually, one service at a time, and keep using some Google services, if you really must - why not?
For most people, I'd imagine "degoogling" seems pretty daunting at first, but if you do it gradually, you'll have rid yourself of Google before you know it. You'll also be supporting a better future for everyone. I don't mean that in an anti-Google way. I mean it in a pro-indie-dev (or small company) way and a pro-decentralized way, the way the internet is supposed to be.
Competition is always a good thing, in the context of goods and services, at least.
I think it's much better in the long term if we support businesses that specialize in doing one thing and doing it extremely well.
It may even be reasonable to think of businesses (companies) like you would well-architected software, where businesses that do one thing well are like small modules designed for a specific purpose, simple and predictable, easy to replace with something better if needed, without affecting much else in your life... while Google is like a monstrous spaghetti codebase with too many entangled dependencies, where changing a single thing has the potential to adversely affect many other things in your life.
We live in a world where services like the ones Google provides aren't just optional, they're critical for so many people. Some have less money in the bank or home than the value of their emails, contacts, media, and whatever else may be stored in Google's systems. Some of those things are priceless.
I agree that it's Google's right to refuse to have/keep you as a user/customer but they should be legally forced to give you back all of your data or at the very least give a generous notice period.
I'm actually hoping that some regulation will be put in place to protect users and ensure that they never lose their data.
Prudent regulation is necessary, but a strong lobbyist group for programmers such as a union or professional association would hurry that along much faster. Developers are end users too, and would be the most likely source of such a push in today's system. Unfortunately unlike lawyers, dentists and doctors, programmers think they're too smart to get organized.