You point doesn't make sense, as you're conflating hypothetical situations with reality.
If I stated on my dating profile "no women over 40", it rules out women over 40. Period. The fact that at one point in time, women who are now >40 were young is hypothetical to the reality that as of today, they older.
If I stated "no fat chicks", the reality is I'm excluding anyone overweight. Doesn't matter if they were thin before, or might be be thin in the future.
If I stated "no Americans", I wouldn't care about the hypothetical situation were a US national moves overseas and changes their citizenship.
If I stated "no tall women", it doesn't matter that someone tall now might have had a late stage growth spurt. If they're tall when they see my statement, the exclusion applies to them.
Putting any clear rules/exclusion that your potential partners have to conform to is the same. Whether it's limiting them by age, race, weight, religion, nationality, height, it's all the same.