Racing bikes. Safely limited by the rider's ability to pedal fast. lol!
I posted safety limited, not safely limited. The words used do have importance.
You know say they say about sarcasm. There's far more about this subject than the superficial, it needs thought.
The reason we have pedelec restriction on assist speed and power is because almost anyone can get on and ride to the machine's full potential. They can have seriously defective eyesight, terribly slow reactions, be subject to blackouts, be deaf, absent minded and anything else you care to think of.
However, with unpowered cycling there is a very real link between fitness and safety at all levels for all cyclists.
The twenty something keen club road bike rider for example has to be very fit to keep up with or compete with the group in all terrains. It follows that at that age and general health level they are the most likely to have good reactions, eyesight, hearing, alertness etc.
As age advances and/or injuries or health problems occur, a decline in those facilities sets in and there's less ability to compete, to ride very fast or ride for as long.
It follows that unpowered cycling is largely self policing by individual ability. Those who can't do, don't do. That is not a joke as you seem to have thought, it's a simple medical fact of life, and it applies to race bike riders too. Competitions are irrelevant, risks are taken then by choice of course,
.