An open division would be a division open to anyone whether Male, Female or trans, non-binary etc. Every athlete would understand that it is an open division and that a person of any gender can participate. There can be multiple ways to do it: 1) Open division and female sex division 2) Male sex division, Female sex division and open division. etc. Its quite clear that while the majority of mtf athletes do not go on to win championships and break records, nearly all greatly outperform their historical performances in the male division i.e. jumps of going from 500th to top ten for example. In reverse, you do not see ftm athletes outperform their historical performances. Therefore as it makes sense to have female only divisions in every sport due to advantages that a man would have in a female division i.e. they would greatly outperform their historical performances in the male divisions, it makes sense to keep the female division a female sex division, especially after all the work done over the last couple decades to get female divisions to stand on their own. Now this does not mean that you just go oh well trans athletes tough luck you can't compete anymore. If you have an open division that all genders can compete in then it does give them a space to compete in whilst also potentially solving the issue of there not being enough trans athletes to make a full fledged division. Also most likely we would see female sex athletes trying their hands in open divisions as well as there are countless female athletes in multiple sports who have expressed wanting to compete against men for example. A question would remain around whether you should roll the men's division into the open division or keep them separate but this would provide a solution for having a division that trans-athletes (both mtf and ftm) could compete in alongside willing female sex athletes with or without male sex athletes.
I understand how open division works. It's pretty simple in theory.
But as in my original post it would "mess up" the game as in the man's division is already very highly competitive even a full grown natural man strive for every small advantages. Anything other than Natural male would stand no chance to compete. Hence the whole thing would become farcical. Accommodating, but it won't be the sports we knew now.
Take for example Athletics.
1. Everyone male/female/MTF/FTM can join
2. How do we decide who goes to Olympic? This will surely goes to Natural Man, what does the other gender have left to compete?
3. How do we decide the qualification? The bar must be set low enough to accommodate natural women.
Again I understand what open division means, i just don't see how it can work realistically.
And I say this because I see that's it is also not fair to let MTF compete in men's division, just like it's not fair to let MTF compete in female division.
MFT in male division : MTF can never win, all things assumed equal
MTF in female divison : Natural Women can never win, all things assumed equal
*When I say all things assumed equal is that they're both professional athlete at their respective sports. Off course A natural Men's amateur Tennis would still lose to Serena Williams.
Hence I think this is not "THE Solution" it's just passing the buck to the MTF, giving them hollow participation without any chance of ever winning
As to 3 division (Female / Male / Open) then we're back to square one. Basically that means MTF would eventually have to start from scratch. A viable solution given time, but I don't think that's viable because who would sponsor a match with only 1 Lia Thomas. And even if in the future there would be more MTF swimming athletes, the numbers would be so small at start that no event could be held.