I believe some of Microsoft's Ergonomic keyboards are highly regarded. I didn't try any of them. Not mechanical but I hear good things. Some of them seem to have a similar tilt to mine. Its not adjustable though and the ergodox folks say you should adjust regularly (I really don't though and I imagine most people don't).
The other big difference is that while the keyboard is split, it is still one piece whereas mine is actually split.
And finally, the ergodox-ez is ortholinear, so instead of key rows that are staggered, the rows of keys are mostly straight vertically, which is supposedly more natural.
At $40ish dollars, it might be worth trying one of the microsoft options.
My keyboard could have been purchased for about $300 without backlighting. It comes with a bunch of different options for the switch, I just swapped mine out (the sockets are hot-swappable so no soldering). I paid more for backlighting because its also got up to 32 programmable layers and you can assign a different color so you know what layer you're on.
There are some slightly cheaper mechanical options. There's a recommendation threat / question thread in /r/mechanicalkeyboards on alternating days where people might be able to help you find something cheaper. I don't know everything so I might be missing a great option for you that doesn't cost a fortune.
One last note, they are not much harder to produce, its just that no one is doing it at scale yet. They are still trying to find the perfect design. Ergodox is one version, there are lots of other split keyboards like iris, artreus62, etc. I think the ergodox is pretty good, but people with small hands might not be able to hit all of the buttons. There are 6 buttons per thumb. Honestly, if I try to use any but the bottom 3 per thumb I have to move my hands significantly, but I assign those to stuff I don't do often. There are other people making smaller keysets, or changing the position/layout to optimize for their use case. If anything ever definitively catches on we might see a mass produced version.
The other big difference is that while the keyboard is split, it is still one piece whereas mine is actually split.
And finally, the ergodox-ez is ortholinear, so instead of key rows that are staggered, the rows of keys are mostly straight vertically, which is supposedly more natural.
At $40ish dollars, it might be worth trying one of the microsoft options.
My keyboard could have been purchased for about $300 without backlighting. It comes with a bunch of different options for the switch, I just swapped mine out (the sockets are hot-swappable so no soldering). I paid more for backlighting because its also got up to 32 programmable layers and you can assign a different color so you know what layer you're on.
There are some slightly cheaper mechanical options. There's a recommendation threat / question thread in /r/mechanicalkeyboards on alternating days where people might be able to help you find something cheaper. I don't know everything so I might be missing a great option for you that doesn't cost a fortune.
One last note, they are not much harder to produce, its just that no one is doing it at scale yet. They are still trying to find the perfect design. Ergodox is one version, there are lots of other split keyboards like iris, artreus62, etc. I think the ergodox is pretty good, but people with small hands might not be able to hit all of the buttons. There are 6 buttons per thumb. Honestly, if I try to use any but the bottom 3 per thumb I have to move my hands significantly, but I assign those to stuff I don't do often. There are other people making smaller keysets, or changing the position/layout to optimize for their use case. If anything ever definitively catches on we might see a mass produced version.