Something I read recently which I think is interesting food for thought:

Did ditching the headphone jack increase the number of people in public who just play their music / talk on speakerphone, because now the alternative is much more complex and expensive compared to simple 3.5mm wired headset?

Before proclaiming that Bluetooth is in fact simple and cheap, consider how your situation may differ from that of the perpetrators

My own memory and current experience on this point is that it used to be far more common than it is today.

I remembered there was a South Park episode where Cartman was being a stereotypical self-absorbed person walking around with their phone on speaker. I looked it up, and that episode came out in 2013. At the time, most phones on the market had a 3.5mm jack. Yet people not using headphones/headsets was an experience common enough to be turned into a joke in the show.

I don't think there's much correlation between 3.5mm jack availability and using a phone's speaker output in public.

"Simple" as you've used it is open to interpretation. I personally held on to wired headsets longer than most of my friends and family. You know what I don't miss, now that I've preferred wireless for a few years? Untangling the cable. Accidentally catching the cable on something and having an earbud ripped out. Picking lint out of the jack. Staying conscious of the length and positioning of the cable in the context of my own movements.

Other than the BT connection process, which is only complicated if you're fortunate enough to own multiple devices and headphones/sets to connect to them, wireless can be a lot "simpler" in actual usage.