I feel that one for sure. I live in San Francisco and was a dedicated cyclist. I had 6 bikes stolen in my first years here. But I was stubborn, got cannier, and kept the 7th long enough for it to look scruffy. Which let me keep it for years. But then it got stolen while locked up behind a 12-foot fence and something went out of me. I just gave up.
I still make occasional trips on the Lyft bikes, which are fine. And I've been thinking about getting another bike. But especially with e-bikes, which are much more expensive and therefore much better theft targets, I just can't sign myself up for years of fretting about theft.
I had a foldable e-bike for two months (was great) in SF before it was stolen. Someone saw me ride up to my house and enter the basement entrance where I kept it locked to a pole in a utility closet. Later on, they grabbed a food delivery bag, told another tenant they were making a delivery, got buzzed into the building, and stole the bike. They didn't get either battery, but I haven't bought a bike since.
How practical is this really? You bring your folding bike into the restaurant where you're eating, into the bar where you're meeting friends, into the gym (it doesn't fit into a locker), into the little corner store with narrow aisles, etc? I feel like taking the folding bike indoors can work for a commute if your office doesn't have dedicated safe bike storage, but I think it falls apart as an overall response to "I'm inhibited from using my bike as my primary transportation b/c it is an easy target of theft"
A Brompton is really small when folded. Smaller than a carry-on suitcase by volume. It rolls on little scooter wheels on the rear rack when folded. I bring mine into all the places you just listed on a regular basis, except for a gym. For a restaurant, it typically will fit under a table. At a bar, if you are at a table the previous thing works. I've also had the bar staff offer to stash it inside the store room. If someone you are meeting up with is DD'ing a trunk works as well. I've never been in a store so small I couldn't roll it in, you can just pull the seat up a bit and roll it in front of you.
Yeah, if I had a commute, I'd think about a foldable, although I struggle with the look. But a big use case for a bike for me is recreational distance riding, which is sounds like they're not great at.
In theory it wouldn't be too hard to take the battery, controller, and a front wheel with hub motor. But I think in practice even the extra few minutes to unplug, remove and reinstall, not to mention carrying all this stuff, would raise the friction to the point where it would be quite a chore.
Having stuff stolen sucks, but with bikes I try to think of it as just a transportation cost. A year's worth of transit passes in my city will run me $1200, so if I buy a $1200 bike and it lasts me a year before it gets stolen, I'm breaking even.
I've had 6 bikes stolen in a quarter century of commuting, but I've saved about $17k over what it would have cost me to use public transit for the same period. More importantly: cycling is enjoyable, I look forward to my morning commute on a bike. Not so much with other transport options.
Unfortunately, I'm not particularly money motivated. What went out of me wasn't a will to spend. It was will to deal relentlessly with all the nonsense.
Dunno if it would work in SF but in London I have an old rusty bike, left outside with a D lock and not many problems - there are always more saleable looking bikes if the thieves are at it.
I think it depends on the kind of thief. The last one I had stolen was indeed a battered-looking thing with low resale value. But I'm pretty sure it was stolen by some low-end criminals who were not very bright or effective.
This was all before AirTags. But thieves are canny, so I'd expect them to be very good by now at finding and removing AirTags.
Supposing I did have one, though, what do you imagine me doing? If I know where a criminal gang has taken my bike, help me understand what you see as the next step.
I still make occasional trips on the Lyft bikes, which are fine. And I've been thinking about getting another bike. But especially with e-bikes, which are much more expensive and therefore much better theft targets, I just can't sign myself up for years of fretting about theft.