The reason Speedos are stigmatised

[Byron]

Yes - the bikini word is not used by guy SWIMMERS as STS says - and briefs and racers have always been suitable terminology in my mind to know what I am talking about in the speedo context.
Bikini is only a two piece worn by women instead of a full torso suit?
Well, no - so many of the girls want to go topless these days that the breast section is discarded. In fact, as demonstrated in several posts on this forum, some guys will also want to purchase ONLY the FEMALE bikini bottoms for something brief to wear (Roxy etc. proving quite desirable).

All very confusing but there was of course a time when the one-piece woollen suit with chest coverage was the 'appropriate' attire for MEN when bathing (see vintage pics of lifeguards for one thing). After that the coming of the Speedo speedo must have been a very avant garde way to display the male physique (even if a compromise was reached with waistlines up to the rib cage).

The Brazilians interestingly take a separate line here.
Tangas were once the minimum brief (the male 'bikini' which was prevalent on the beaches of Rio) but , almost overnight , tangas became only for the girls and the guys would wear instead the ubiquitous and larger sungas (and to translate that into non-Portuguese terminology we might say square cut speedos for those).