Your only focus on everything seems to be a whether it is sinful or not.

Shorts are the clothes of children,

The reason for this is 1) if it's not a sin for all men, that means the action is a morally neutral action.  2) Morally neutral actions CAN BE sinful based on circuмstances, or intentions, or not sinful at all.

If we define "shorts" as a clothing item which covers the waist down to the knees, then you're wrong.  History is full of examples where men commonly wore such attire 1) with no danger of moral scandal, and 2) with no insinuations of de-masculinity.
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German Lederhosen, Scottish Kilts, European 1700-1800s dress, Roman Centurian battle gear, etc.

Thank you.  People really need to start thinking about things instead of just mindlessly repeating something that was once heard (likely taken out of context) from Bishop Williamson.

Last Tradhican posted three times to Ladislaus:
By the way, by your only WHY, immodesty, you would not have a leg to stand on with regard to women wearing loose fitting pants. Bp. Williamson also taught that women can't wear pants, and it was not only because of immodesty like for instance tight form fitting jeans, it was because pants are the clothing on men. In this case of the shorts, there is a similar WHY they should not be worn by men,  it is because they are the clothes of children, my #2 above.

How about the French tights, they covered everything and were worn by everyone? Those are all examples of attire of a particular country and time, everyone wore them. Nobody would wear them today outside of those countries and times.

In our times, the late 1800's till present, shorts have not been the attire of men, but of little boys only.

Those of you that gauge shorts strictly by sin, how do you respond to women who wear loose unrevealing pants? That's another well known teaching of Bp. Williamson, that women should not wear any pants.

German Lederhosen, Scottish Kilts, European 1700-1800s dress, Roman Centurian battle gear - there is nothing EXTREME about these examples.  These were all worn by men of all types, for decades.  There has never been any Catholic condemnation against this fashion, therefore your "principles" don't exist.  (That, or you don't understand what a principle means, which must apply to men, of all times, in all situations).