Both over reving and lugging(over propping)can cause bearing failure. Over reving can lead to bearing skate which due to lack of lubrication will flatten the bearing and kaboom. Lugging does somewhat the same thing. Too much pressure on the bearing during power stroke can push the bearing out or flatten it especially if the lubrication is not adequate.
Hypereutectic pistons(cast pistons) are limited to 3500 fpm. Forged pistons can safely reach 5500 fpm without the skirts blowing off. See this link to understand piston speeds. https://www.musclecardiy.com/performance/understanding-piston-speed-in-high-performance-engines/
Lugging or over propped is not likely to hurt the pistons if the fuel and lubrication is within spec.

Lugging or over propped is not likely to hurt the pistons if the fuel and lubrication is within spec. This is where you went wrong. Lugging is the act of applying more throttle and not getting the RPM`s. Impossible to maintain a correct fuel to air ratio with a 4 stroke or a 2 stroke. Lots of variables. https://www.youtube.com/watch?v=soJea7xEt-8

Wow! if it's on you tube then it must be true. What I'm saying is: Piston failure from lugging is far less likely than bearing failure. Anything can happen in an internal combustion engine at anytime due to a million things.

Like if you say it. You went way out in left field on the guy trying to decide on buying an outboard based on this readout. Good Luck and Merry Christmas

Not to mention tech doesn't spell very well. Straight prop shaft and ran great would be proper spelling. If you can't take it to someone you feel comfortable with checking it out,I would move on. Alot of red flags here.