My thought on that is your rough revenue over infrastructure + development + maintenance cost is what matters. There is google/facecrack in one corner of that problem space and a chain smoking accountant with a ledger in another corner. You are likely not in either of those places.
You can get away with a lot less dedicated infrastructure staff if you use your cloud provider as more than just a glorified overpriced colo and actually take advantage of their managed services.
Just to keep comments from going off the rails and everyone says it’s a mistake not to have dedicated “infrastructure people”. I’m a software engineer still by choice, but I have turned down a few offers as an “AWS Architect”.