I've seen this exact same thing happen to a company I used to work for. They had an enterprise B2B app that had extremely low traffic. The Heroku app worked fine but the CTO spent a year building a super complicated AWS stack as an exercise in resume building. After the AWS stack launch filed miserably and we had to switch back to Heroku the CTO quit and still has "migrated company to infrastructure as code AWS stack" on their Linkedin profile.