The average lifespan of an established corporation is only about 20 years. The average lifespan of a new company is only 10 years. So anything that lasts longer is living on borrowed time.
It's like reaching your 50s-60s which when the 2nd derivative of death goes into overdrive. Only by surviving that period is there evidence as proof of life that you are doing something right or had good genes. The same for corporations and then 10-20 year period.
So Google in exactly in this cusp. They may not survive it but "that will be that" without moral or ego judgement. If they die now, it's simply that they didn't not find the magic elixir of life or purpose or business model. I think the handwriting about that is already on the wall - they did NOT and we are merely watching its decline. It just happens.
The best way to avoid the problems of dependency on an entity is to not become dependent in the first place.
Just like allowing one to be coddled and never growing up is a bad long-term strategy because that person's parents won't live forever and they will survive parents alone. They will be ill-prepared to do without but nothing in this universe can undo that reality once it happens. The answer is always for a parent to make sure your children are independent and well-prepared enough to live without you. Not doing that is misparenting.
In the economic sphere, blindly becoming dependent on only one technology or vendor is similarly an error on your part. Either create alternatives or find ways to live differently that do not require it in the first place.