Make docs clearer on custom VPCs

[SkalaNetworks]

This phrasing in the docs is not very clear. From what I understand, custom VPCs cannot have subnets with natOutgoing: true because they simply don't route outside the node. The only way to have external connectivity with a custom VPC is through a NAT gateway.

So what is this sentence trying to convey?

Subnets under custom VPCs do not support distributed gateways and centralized gateways under default VPCs.

Does that mean subnets under custom VPCs can't use distributed gateways AND centralized gateways can't be used by subnets under default VPCs?
Does that mean custom VPCs can't use both distributed and centralized gateways? But then why mention default VPCs