Many/most teams internally using AWS use CloudFormation; an AWS service I was a part of was almost entirely built on top of other AWS services, and the standard development mechanism is to use CFN to maintain your infra. You only do drastic things like "stringing CLI calls" if there's something missing from CFN and not coming out soon enough, in which case maybe someone writes a custom CFN resource and you run it in your service account.

Depending on how old the service is, the ownership of the CFN resource may be on the CFN service team (from back when they white-gloved everything) in which case there are massive development bottlenecks (there are campaigns to migrate these to service team ownership) or more often the resource is maintained by the service team itself, in which case the team may not be properly prioritizing CFN support. There can be a whole lot of crap to deal with for releasing a new CFN _resource_, though features within a resource are relatively easy.

On my last team, we did not consider an API feature delivered until it was available in CFN, and we typically turned it around within a couple of weeks of general API availability.