That wasn't cautionary at all it's just a fucking advert.

real mice have balls

All hail trackballs ٩( ᐛ )و

I’m getting proud parent vibes from your creation.

I have that same mouse for work stuff. Care to share the model for printing?

The IT manager at my previous job used this as a security feature.

People thought that because he was the IT manager he could just get another mouse, so they'd just take his when they left their mouse at home and never return it.

So he got a left handed vertical mouse even though he is right handed.

Nobody steals his mouse now because it is vertical and cannot be used in the right hand.

My Logitech MX Master 2 has a decent amount of angle without being vertical, maybe something like that is what you're looking for?

Mx Ergo, best of both worlds

Really love the feel of my Logitech G pro tbh. Super clicky, light, and smooth. The texture of the material is great too.

It's not at all ergonomic bc it is an ambidextrous design but it hasn't bothered me yet and I use my PC way more than I should.

Touchpad keyboard gang.

The two I've used are the one in the image (it's from Anker, I forget the model) and Logitech's MX Vertical (they have a second, smaller version if the original is too big). I've been maining the Vertical the past 4 years for work and personal use.
Both have pros and cons:
Anker is cheaper. ~$35 vs ~$80. Also has a built in slot to put the receiver in when not in use.
It curves with your hand more than the Vertical.
Anker uses easily replaceable AAA batteries. Usually lasted me about 3 months before I needed to swap them. I only used it for work though.

The Vertical can connect to 3 different devices (1 dongle, 2 Bluetooth) whereas Anker is limited to whatever the dongle is connected to.
The Vertical is made of better feeling materials; like a rubber for extra grip vs hard plastic with the Anker.
There's a USB C port to charge its (not easily replaceable) battery.
Edit: Vertical won't go to "sleep" like the Anker will. If the Anker isn't touched for X minutes, it will go to sleep and you'll have to click one of the switches to wake it. Otherwise moving it won't move the cursor. Not that huge of an issue, but definitely annoying if you don't know what's going on.

However, there is a design flaw with the Vertical. Logitech run their wireless mice at very low voltage and current to save on battery. That's how they get a 240 mAh battery to last for around a month of heavy use.
The problem with this is you need to use particular switches, otherwise corrosion starts to build up on the connectors. This corrosion leads to incomplete or missed clicks, phantom double clicks, or it's impossible to hold a click.
From what I remember, standard switches are designed for 5V, since that's what wired mice normally run at. But modern wireless mice operate around a tenth of that. Logitech never made the switch (heh) to switches rated for that low voltage. At least not when I bought mine.

My Vertical had that issue. And rather than buy an entirely new mouse, I went in, desoldered the old switches and replaced them with new ones (I think I went with Kale's light blue switches). I did that in summer '22 and haven't had any issues since.
The rubber material is also showing wear and tear where my fingers sit, but that's just cosmetic.

I got the Anker one for my mom holiday '22 and she's been happy with it. It helped the discomfort in her hand.
Both mice improved the stiffness in my right hand, so either one will get the job done. I will also say that there is a bit of an adjustment period. Surprisingly, changing the angle of your hand kind of throws you off and takes some getting used to. Before my office went remote, my coworkers would avoid using it because it wasn't easy for them to switch to for just a short period of time.

Hopefully this info is helpful. I can try answering any questions you have on them, but those are the only two I have experience in.

Edit 2: Phrasing

Depends what you expect. On a pro tournament level, nobody will use a vertical mouse. Usually they are a little bit heavier than regular mouses, plus they have a slightly higher center of gravity. This makes them a little bit more "wobbly" during ultra fast movements.

However, for regular playing, they work just fine. I don't play on pro level, but okay competitive shooters almost daily, and I haven't noticed any real disadvantage. And it helped my wrists enormously, because I'm a full time office worker as well. I decided a couple years ago that the small theoretical disadvantage is not worth the risk of RSI and have been using the cheap CSL/Anker/whatever vertical mouses since. Only very recently I boughta second, regular mouse with more thumb buttons, useful for some sim games I play. I now tend to switch fairly randomly between the two, which probably is even better for hand and wrist.

Additional info: getting used to a vertical mouse takes much less time than most people expect. Yes, it's weird at first, but start working or gaming and you'll stop noticing the different posture very quickly.