Agreed, hat was the ideal traditional lineup construction. But in the age of analytics that has been changed fairly significantly for some teams.. With every notch in the batting order getting approximately 20 more plate appearances over the season than the next one that becomes the prime consideration. For example Aaron Judge over the course of a season will have approximately 40-45 more plate appearances over the season batting second rather than third.
Speed is not that important for #1 - it's a bonus - but OBP is more important. Of course if its Kirk type speed that is an issue.
#2 in the traditional sense (which was often a fairly light hitting player who didn't striekout) is largely obsolete.
Of course a guy like Raines, Henderson, Alomar will fit at the top in past or current times. But last year, a guy like Raimel Tapia may have been considered to leadoff in the 80's, while the notion wouldn't even be considered today.
For example Aaron Judge bats 2nd exclusively. Shohei Ohtani spends half his games batting 2nd. Vlad spent a fair amount of time there in 2021 and 2022. Seems to be between #2 and #3 for the best hitter.
Another reason is that teams played small ball a lot more. Leadoff hitter, with a big OBP, gets on and either, with his speed steals second or the light hitting number 2 man moves him up with a sac bunt. Then, the best hitter, #3, knocks him home. Then big bopper, #4, clears the bases. That was the thinking.
But, as you've adeptly explained, the thinking has changed. Nowadays there are way more guys who can knock it out of the yard, so that many players can hit 4th while you still get those extra at bats for your very best hitters guaranteed to bat in the 1st inning.
I also think that the DH changed things as well. Without the pitcher being a totally wasted at bat, a guy like Kiermaier can bat ninth and now your best hitters at the top have way more chance of coming to the plate with a man on. Think of how many innings ended with the pitcher being the 3rd out and the leadoff hitter starts the next inning with nobody on and they have to play small ball again.