In my opinion it may be true or half true. It would help if you had stated why you "dropped it off".
First off, cutlass bearings are typically associated with inboard engines driving a shaft that exits the hull of the vessel. But, the larger Honda outboards do have a bearing supporting the mainshaft at about midpoint of the extension case. There have been issues with some of those bearings so perhaps that's what they were referring to?
Additionally, outboards DO develope problems with corrosion in the thermostat housings and catching that early and dealing with it is something I could agree with.
The thermostats themselves are too often neglected as well and keeping them in good working condition or replacing if needed is critical to your engine's longevity.
So, these things could be perfectly legitimate IF there is a need to address them.
It's really up to you, as the owner, to be aware and beware of these aspects of your equipment and do your best to ask enough questions to protect your interests.
If you ask those questions...why, where is that...what does that do....how long...how much.... guarantee?....but aren't comfortable with their answers, you should probably look for another repair facility that you can better communicate with.
Good luck.