100,000 dollar multi engine boat no longer exists. 21’ Boston Whaler Montauk with a 200 hp single engine is well into the 80’s. 
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The 45’ three engine rides are near a million. Easy to drop 1.5 million on 45’+ center console rig.
That map may be a bit misleading. Michigan does not even require training once you reach the wise old age of 16.
Get the registration number of the boat. We reported a local no wake/100 foot rule violation to the township police and they issued a $100 ticket. The inland lakes around here are sometimes patrolled by county mounties.
Worst case I had was on a 20 foot wide stream in a state forest, an almost wilderness experience, got passed by two jet skis. The water was shallow enough that I suspect they had to stay on plane to avoid grounding.
Of late there has been a big increase in wake boarding boats that are designed to produce wakes, and wake surfing (no rope) is becoming a thing. The boats have huge engines and tanks for hundreds of pounds of water (no bags needed) to increase displacement. Current regulations on safety and shoreline erosion were not formulated with these in mind.
Wow, Michigan does seem to have a more convoluted set of laws regarding who needs training. I do think you may have (understandably) misread the rules though, at least regarding 16 year olds.
For boats, generally:
Those born on or after July 1, 1996, may operate a boat legally only if they have been issued a boating safety certificate and have it on board the boat.
[That’s currently anyone age 25 and under.]
and specific to PWC:
Those at least 16 years of age and born after December 31, 1978, may operate a PWC legally only if they have obtained a boating safety certificate.
[That’s currently anyone age 43 or under.]
Yes so much fun. I also love watching unsecured kayaks fall off cars at highway speeds, new skiers knocked down trying to get on a ski lift, tourists getting lost on the NYC subway, and almost any other misfortune that’s not my own. Such fun.