These toilet roll holders in public toilets. I hate them...tiny squares of paper that come out one at a time all scrunched up. You have to straighten them out one by one to have a nice neat wad for a decent wipe.
They are so rubbish. Just because it's in a toilet, that doesn't mean that I want a bog roll dispenser designed like a bum hole. And you have to grip them really close to the bum hole, too, to stop it from ripping, which can't be very hygienic at all.
Taps that require a hand on them to keep the water flowing and stop the instant you remove your hand. What idiot got to the position of being a tap designer without understanding the absolute basics of washing your hands in running water - and that most humans only have two hands, so they don't have a spare one to keep the tap working and then rotate to wash two hands at a time.
Also, you don't see them too often, but those stupid light switches in some public bathrooms - where you push in the round button and they give you 15-20 minutes of light before they turn off. You're either in there for 2-3 minutes then out, meaning that an unoccupied room is lit up unnecessarily for 10 minutes or more; or you're having a shower, in which case it might just go dark shortly before you've finished and leave you naked and groping around in the cubicle.
I hate the whole constant beeping when appliances have finished thing, too - like it's a fire alarm and not just a washing machine that really won't do any harm at all if you don't empty it for 20 minutes. Who designed appliances to be arrogant and egocentric? However, you can often switch off the 'helpful' nagging beep mechanism - enter the make, model and 'beeping' into YouTube, and you may well find a very friendly person has uploaded a clip to show you how to stop it.
I very much agree with the PP complaining about the whole 'if it ain't broken, break it' ethos - just because somebody happens to find something old-fashioned - although, with hand brakes, I once hired a van where the handbrake was to the right of the (right-hand drive) driver's seat, so you had to clamber over it and try to avoid it catching on your clothes every time you got in or out. Scroll bars are another one of those: in the old days, you had a nice thick scroll bar at the right of your computer screen, waiting for when you needed it; but now, it disappears when not in use, so you have to wave your mouse around so as to tempt it out again - and then, when it does come back, it's a skinny little thing that requires really careful, pinpoint accuracy.
Laptop keyboards, as well. We used to have really decent mechanical keyboards, with proper key 'travel' but somebody decided that ALL laptops had to be a whole load thinner, meaning that they were replaced with those rubbish membrane button things. Even on some very high-end laptops. Fine to offer the choice, but as so often, 'they' decide that the new way is better and so you lose the good old sort and any real choice. Nice option for those who want a light, skinny little thing to carry ack and forth to the coffee shop; just utterly pointless for those of us who only ever use it at home, plugged in.
I know it's not an 'item' as such, but two kinds of software: those useless captcha things, where you have to tick every square with a bus in it, but there are also some trams or trains, deliberately designed to thwart and frustrate those with poor eyesight - if we need to prove our humanity, why aren't those simple 'I am not a robot' tick boxes not used as standard?
And passwords: I get that 'stronger' is better, but it really defeats the object where nobody can remember them without writing them down or having to request a 'reset password' email every single time. Then, as you're typing them in, websites will panic in alerting (and patronising) you that the password is 'incorrect' right up until you've typed the last character. Now, if there were a single button, standard on all keyboards, that could serve as my password with just one press.... it wouldn't be a very secure one, now, would it?