I get the point you are trying to make, but as AWS offers many services, I don't need a sysadmin for a DB (RDS, Dynamodb, ElasticSearch, S3) or for APIGateway nor for any coordination between systems (SNS, SES)
True serverless let's me offload that cost to AWS instead of having a sysadmin
Who maintains the database, schema, updates? Application deployments, testing, qa, updates? There's someone doing the job, even if it's fewer people, or someone with multiple hats.
True serverless let's me offload that cost to AWS instead of having a sysadmin