It's mostly an ego thing and another way of making women vulnerable tbh.

There's men on the internet that admit they see women that ask them out as "free meal tickets", that they rarely respect them nor think they're feminine because they're "assertive", that they tend to be less attractive, that it signals to them that they never have to try with a woman like this, etc. On the reverse, a lot of women that did so take months to realize he's not that into her in spite of this being blatantly obvious from the beginning. That person noting how she's run into an issue with men dropping the ball in terms of effort is right; endless statistics and research back it up.

So, in other words: a lot of men say the ask out thing because they overvalue getting access to women--not so much being with one or nurturing a relationship.