If a company acquires Chrome, they don't have many choices: re-establish Google integration deals (so the divestiture would be pointless), replace Google integrations with their own (becoming just another Chromium distro in a sea of Chromium distros), or just monetize the existing userbase.
A Chrome acquisition doesn't include unlimited control over Chromium. Chromium is open source, with contributions from many organizations (who retain the copyright to their contributed code). Google can only sell what it exclusively owns: the brand, infrastructure, signing keys, etc. The real force behind Chromium is having a critical mass of engineers all pushing in generally the same direction. You can't necessarily just buy that, especially when you wouldn't own exclusive rights. Any other company is free to poach engineers and fork the project.
Edited to add: if Microsoft sold VS Code to, say, Oracle... don't you think that another company would leap at the opportunity to fork the project? Would the userbase and the thin layer of closed-source Microsoft customizations really be worth that much?