In my experience, bars these days (in the era of dating apps) are less a place where straight people pair up with strangers, and more a place where they:
Go on a first/second/third date with someone they know from a dating app or mutual friend or interest group, and maybe hook up with that person
Go with a friend group, and meet someone through a mutual friend, and maybe pair up with that person
But fwiw, it still seems reasonably common for people pair up with strangers in bars/clubs where I live. I don’t think bars/clubs are the perfect solution to meeting people romantically/sexually, but they have some advantages:
Alcohol makes people more willing to approach strangers, open up personally, and judge potential partners less critically
Bars/clubs (at least in major cities) are mostly filled with strangers you won’t see again, reducing the (perceived) costs of rejection or committing some faux pas
Bars/clubs being dark and noisy makes it easier to approach someone without a lot of other people observing you
In bars and especially clubs, (good) music creates an atmosphere where people (who like that music) feel mildly intoxicated
Clubs in particular involve quite a lot of moving around (across/to/from dance floors, bars, toilets, and chill-out areas) that create opportunities to meet/interact with strangers
That said, I think 10+ years ago bars/clubs were more of a place where people paired up with strangers. My sense is that this has changed largely due to dating apps, not by making it less acceptable to approach strangers, but more that dating apps offer an (often superior) alternative way of getting dates, which means people go to bars/clubs less to meet strangers and more to spend time with friends/partners. And even if a person is still interested in going to bars/clubs to meet strangers, it is harder when most other people are just there with their friend groups and not interested in interacting with strangers.
(Bars/clubs for gay people, and especially gay men, are different. There, it is still pretty common with random hook-ups, I should think.)
In my experience, bars these days (in the era of dating apps) are less a place where straight people pair up with strangers, and more a place where they:
Go on a first/second/third date with someone they know from a dating app or mutual friend or interest group, and maybe hook up with that person
Go with a friend group, and meet someone through a mutual friend, and maybe pair up with that person
But fwiw, it still seems reasonably common for people pair up with strangers in bars/clubs where I live. I don’t think bars/clubs are the perfect solution to meeting people romantically/sexually, but they have some advantages:
Alcohol makes people more willing to approach strangers, open up personally, and judge potential partners less critically
Bars/clubs (at least in major cities) are mostly filled with strangers you won’t see again, reducing the (perceived) costs of rejection or committing some faux pas
Bars/clubs being dark and noisy makes it easier to approach someone without a lot of other people observing you
In bars and especially clubs, (good) music creates an atmosphere where people (who like that music) feel mildly intoxicated
Clubs in particular involve quite a lot of moving around (across/to/from dance floors, bars, toilets, and chill-out areas) that create opportunities to meet/interact with strangers
That said, I think 10+ years ago bars/clubs were more of a place where people paired up with strangers. My sense is that this has changed largely due to dating apps, not by making it less acceptable to approach strangers, but more that dating apps offer an (often superior) alternative way of getting dates, which means people go to bars/clubs less to meet strangers and more to spend time with friends/partners. And even if a person is still interested in going to bars/clubs to meet strangers, it is harder when most other people are just there with their friend groups and not interested in interacting with strangers.
(Bars/clubs for gay people, and especially gay men, are different. There, it is still pretty common with random hook-ups, I should think.)