Apple bought Beats, and decided they could sell more of the wireless Beats headphones if they removed the headphone jack.
Other companies copied Apple because they wanted to get in on the wireless headphone sales.
It’s harder to sell wireless headphones when the headphone jack exists.
Rather than including basic $2 earphones with the phone (which many people would even be fine with using), or hope people might buy your brand of earphones for $20-50, they sell you wireless headphones for $150-300.
Removable batteries and ease of repair make phones last longer, and therefore people are less likely to buy replacements as frequently.
They used water resistance as an excuse to stop giving people removable batteries, and to make phones difficult to disassemble/repair. “Oh, but we have to make it difficult to repair because it wouldn’t be water resistant otherwise”. But what if I don’t care whether it’s water resistant and would rather just have it easy to disassemble?
When everything is glued in rather than using screws, removing the glue is difficult, and so is re-gluing it back together.
Screws make it easier. And having the same size and type of screws for everything makes it even easier still. And so does not placing screws in spots that are difficult to physically fit a screwdriver because there are other parts in the way.
And Apple have never allowed you to use a MicroSD card, because then it wouldn’t be so easy to sell models with more storage for way higher than it cost to include that extra storage.