I’ve been riding clipped in since I was 11 or 12, and all I did back then was MTBing.
I like it, I’m used to it, and the pedals have got better at shedding mud and hence unclipping at a more predictable level of force. I’ve only ever had issues due to them when on very muddy rides before the pedals got better at mud shedding, um, and when going off the back when I was learning to wheelie!
That said, I practiced clipping/unclipping on the driveway a lot before I went out, and it took years before I was really used to them. I don’t think you were misled re. better shoes being available, but I’m sure you could find something warm and waterproof that was suitable for flats if you searched hard enough. If you don’t get on with them, that’s fine, just use your flats.
The only place you have to use clipless is on the velodrome, and if you need to unclip suddenly there something has already gone very wrong.