I think DO is the clear winner for K8 - easy to deploy, a lot of tools for developers, and especially 2TB of free egress with every node. GCP egress pricing is outrageous, almost ten times DO egress pricing, and without the 2TB free allowance. That kills GCP's potential for attracting majority of web apps and developers. "Our network is excellent, we have great engineering" does not justify the the great difference in price and continued usage costs.

To illustrate with a simple example: If a middling WordPress site is going to pay ~$50/month for a simple WP deployment that is equivalent to a pretty standard and functional host's ~$5-10 plan, and then pay another $10-$15 monthly egress fees, they will just not use GCP. And this, with WordPress sites mostly using Cloudflare and CF caching a lot of stuff for them and delivering the cached assets from their own network. And GCP having peering agreement that reduces egress to CF.

So, despite the very visible attempts of GCP to attract broader segments of the Internet, publishers and developers, they can not go anywhere with those outrageous egress costs.

If someone is making a very sensitive application like a medical application, or a game that requires the minimum ping and excellent network quality, maybe GCP could be justified. But for a majority of apps GCP is too expensive for the scarce advantage that brings over the other providers.