The idea of making changes doesn't scare me at all, and shouldn't scare any competent developer or DBA.

The idea of trying to make changes without the resources that are clearly needed to make them successfully puts me into a stubborn mode where I won't start the changes unless/until the resourcing is sorted out. Maybe some people are scared of benig stubborn in that situation? Maybe they feel that there's a requirement to do the impossible and that makes them scared and whatever they do will be wrong, and that gets them scared. When management is insisting on change but refusing to budget for doing it the people under those managers could reasonably think that they are in a rather unpleasant situation: they can refuse to attempt the changes, which may get them sacked (it never got me sacked, although I did it a few times); or they can start trying to do the changes, which probably will get them sacked if they don't jump ship before it all turns into a disaster.