You're likely right, but that's the sales pitch. I don't believe it for the most part. I've been at two companies that made a cloud "transition" while I was working there over the last decade and they're always surprised, shocked, and immediately spring into cost cutting measures as soon as they get the bill. (Meanwhile I'm there like "how could they not see this coming?")

Another point worth making is that if you already have an IT department, a software development staff, or software is a large part of your business... development and testing in the cloud have big, big costs versus running a test environment on your own hardware. And you can try to skip it, but enjoy testing the actual system in production because it will not be the same.