I have been either part of or opted out of well over a dozen - I have a policy of never leading “lift and shifts” (and never staff augmentation).

Once you actually sit down and come up with a project plan with your PMO, a cloud migration is hardly ever worth the effort unless the destination cloud provider is backing up a shit ton of money for not only operational credits but also for internal AWS Professional Services (where I worked when I was inside AWS) or an outside partner to help (current employer).

Hell even certain departments at Amazon would never go through the effort of migrating to AWS from the legacy CDO infrastructure.

The risk of regressions, the refactoring, the retraining, the politics, etc are hardly ever worth it.