It will take decades, Google even alludes to that on their site, but to be honest, the insane power of quantum computers is worth it.

I don't think it will be like fusion in the sense, that most experts understand this task is complex and know how long this will take unlike fusion. Mostly No one thinks quantum computing will happen in the next 7 years.

There will be more computing advances in the near future to look forward too.

Maybe then we'll have a tech points cheat code for our civilization