It takes years and millions of dollars to switch ERP platoforms.
Buy the company for...what a year or two (or even less) worth of contracts equals.
Fire all the developers. Keep a skeleton support staff. Fire sales/marketing. In-house everything else. Then just keep getting paid by customners until they all finally go away.
Over the last few years, I've transitioned projects between Jenkins, Travis, AppVeyor, CircleCI, GitLab and others. In most cases, the logic had mostly been factored out in to shell scripts and batch files. Telling one CI system to set up the build/test environment and run that script is pretty much the same as any other.
And this might be the reason why this layoff has happened. What future did Travis have as a business? What was its growth potential? How many paying customers did it have? When everything you offer is done better, often for free, by your competitors and customers can easily set up their own self-hosted replacement if they choose, I'm a bit skeptical that the business was worth that much in the first place.