100%. I'm generally pretty optimistic. On that point, I've been sticking with Z-wave for about 10 years always thinking "maybe soon it will be fixed." . Long ago, said to myself - maybe Z-wave plus 500 series will solve the routing issues of Z-wave 300 series. It didn't, but in crept the optimism with the hope that maybe the 700 series would. It didn't. I reluctantly learned to deal with "ghost nodes" and other device issues, but it shouldn't be that way. And don't even think about S2 security (unless you have to as with locks). But there was the hope -- maybe just another z-wave controller firmware update to do the trick. But that didn't quite materialize, so there was the hope that the 800 series might do it. No again. About a year+ ago, I reached the point where I won't buy another Z-wave device ever.
Zigbee is much more reliable- at least the plug-in devices. But zigbee devices generally don't have the equivalent of Z-Wave Central Scenes (a significant missing feature) - there are a couple of devices with something like that, but its vendor non-standard. Matter solves that by bringing in the Generic Switch device type supporting taps (If only Zigbee had added this years ago). However, at this point, Matter devices are still too unreliable. Last weekend I replaced all my Wifi mesh routers with Google Nest Wifi Pro 6e - adding 6 more border routers, plus latest Wifi. Made Matter / Openthread a bit better, but devices till drop off the network. Maybe there will be a fix soon. Maybe not - I have to learn not to be too much of an optimist to avoid disappointment.
To be clear, I don't see these as Hubitat faults - but it certainly all holds back the market and limits what you can do and the market size.
This is not the primary market, folks with 100+ devices. It's an edge case. Z-Wave works well for smaller device counts, and systems not constantly being added to. Now, this is not your use case certainly, but it helps to keep some perspective about this.
Both Zigbee and Z-Wave are pretty reliable for most users. Those who have the most problems are those pushing the envelope in terms of complexity, number of devices, etc. The mainstream market is not impacted by the frailty at the edges.
I'm one of the early adopters of multiple hubs to spread the load. I was exclusively ZWave until 2 years ago when I really had to have a ceiling fan solution and at that time the Zigbee based Hampton Bay Fan Controller was the only perfect fit. However, that came at a cost of having to deploy one Zigbee repeater per fan.
I don't remember the exact day I added a second Hubitat Hub, but I do know that it was a C-4. I chose to split my house full of devices across the two hubs based on geography.. Upstairs, Downstairs. The stairway itself gave me a puzzle because, of course, some of the devices I had names "stairway xxx" existed downstairs at the bottom of the stairs, other portions were at the top of the stairs. I made a decision: stairs are downstairs devices and have stuck with it.
The big line in the sand I drew for myself was limiting Z-Devices to 65 per hub. No empirical reason, just that I had 65 devices when I got that first C-3 and they worked fine. By the time I decided to get a second hub, I was closer to 80 devices and knew there'd be more. In other words 65 worked so I knew I could set that as a limit.
We found that people with 100+ Z-Wave devices tended to have issues with Z-Wave, and those with 65 or less not so much. Just because the specification says Z-Wave can have 200+ device addresses, doesn't mean that a real world mesh with more than 65 devices will work well. Toss in older non-Z-Wave Plus devices, and problems are going to happen. Same with multiple S0 devices. The realty is that Z-Wave is not a strong technology. It works OK for smaller installations with newer devices.
I also found out having a large bank of Z-Wave switchs is also a problem maker. We put 8 switches on a wall (2 rows of 4) for a great room that was wired for central lighting control and talk about traffic loss on Z-Wave like I have never seen before. As stated, fringe cases like these are always going to stress the technology and usually the manufacturer doesn't test for them.
For many of us with C-7's with an antenna mod or the C-8 have found that a very large percentage of our ZWave devices are direct and therefore function as hub and spoke.
For example, one of my ZWave hubs has 32 Devices of which 28 are direct. The other 4 are one hop.
In other words, 28 of those devices are working in Clear Connect mimic mode And mimicking Clear Connect is the highest praise.
And mimicking Clear Connect is the highest praise. 
