Admittedly for $100 you might have to choose one or the other (though I used a $12 ergonomic mouse from Amazon for years until I switched to a trackball, and I loved it) - but if your job is computer based, you really should consider switching to ergonomic equipment.
Your average keyboard and mouse setup is absolute murder on the wrists in the long run - if you spend more than a couple hours at the computer every day without ergonomic equipment and your wrists don't hurt, then it's only a matter of time.
Granted, it's not just about buying a cool new keyboard and mouse - you also need to cut out bad habits like wresting your wrist on the table while typing and so on, but a good KBM will help you build those habits naturall
I'd advise looking into a cheap, older mechanical option as best you can and cleaning it up yourself. If you want it to last you're better off investing either that time or that money into one to really make it count. Ergo boards are less in demand than a standard keyboard so they'll tend more expensive but they'll pay your hands back kindly
If you're willing to shoot a bit over the $100 budget listed on the post, "Alice style" mechanical keyboards are getting quite popular. Here's a cheaper option but certainly not the best, might be worth some research https://en.akkogear.com/product/acr-pro-alice-plus-mechanical-keyboard/
I believe whether or not you need it is a posture and personal physical setup thing.
I've been using mouse and keyboard extensively for way over a decade. I don't think they're what you'd call "ergonomic". I haven't had any wrist issues.
I bought a bunch of mechanical keyboards. I had "the mech fever". Several hundreds of dollars.
I bought a microsoft ergo keyboard on a whim 3 years ago and never looked back. It's perfect. I can type faster and have zero discomfort. I can't think of how it could be improved.
Yeah Mechanical keyboards are great, but they're often not ergonomic at all, particularly the "rectangle" style ones.
I've got a moonlander on a 45deg tent and it's absolutely amazing, though I'll admin it definetely cost more than $100. I have used the keyboard I think you're referring to though, and it is definetely an amazing value for the money