This is one of the biggest features that you appreciate a lot when you dont have it, and makes global apps incredibly easy. Softlayer has a similar network with default region peering but not as advanced.
Of course anything can be setup using custom VPN but this is a lot more work and will never be as easy, reliable, automated or cost effective.
That being said, AWS is rolling out automatic VPC peering, running on their own private backbones between regions so there should be functional parity soon, although with different price and performance compared to GCP.
It's a feature they have. It might not make up for other parts of their platform that don't fit what you need but we've found their servers to be efficient and their support is quick and helpful.
They're overshadowed now by the scale, efficiency and managed services of the major clouds but can still be useful if you're running on their dedicated machines. Last I checked, Keen.IO runs on softlayer.
Digital Ocean is a far better alternative if you don't want to use the other bigger cloud providers, quite frankly. AWS dedicated servers are also far less expensive and you get more bang for the buck. m4.2xlarge, for example, is the most comparable hourly offering based on memory and CPU cores to SL base dedicated server and outperforms the hell out of it. See here:
Of course anything can be setup using custom VPN but this is a lot more work and will never be as easy, reliable, automated or cost effective.
That being said, AWS is rolling out automatic VPC peering, running on their own private backbones between regions so there should be functional parity soon, although with different price and performance compared to GCP.