My two cents as a Visible customer (actually, all 4 cell phone users in my household (yes, I'm not yet nomadic)) for the past 10 months:
Caveat: most of my use occurs within a 5 mile radius of a point about 3 miles from a 40K town (city?) in SE AZ. Definitely not "in town" (rural suburbia?). At this location, on my phone (BYOP Google Pixel 5), I have "LTE" coverage (never "5G"), I get 60/15/8 Mbps down (best/typical/worst). If I drive 3 miles further from town, I hit a spot (a favorite restaurant) where I get 135/90/8 (also LTE).
I use my hotspot regularly but seldom daily. Mostly to fill in when my 5G cell-based T-Mobile Home Internet has an outage or severe slowdown. I bought a GL-iNet router in hopes of getting same speeds on hotspot as I get on the phone itself, however none of my attempts (1 month ago) to modify TTL on the router firewall (all internet-suggested permutations) achieved this goal. This result aligns with those achieved by some users on the iRV2 forum thread mentioned earlier: works for some, but not for others. So I use hotspot directly from my phone. This has not presented a problem in practice: it works, I'm only using one device with hotspot at a time, and I can place my phone in a wireless charger while operating in hotspot mode, allowing hours of hotspot use w/o draining the phone battery too severely; also, switching to use the hotspot w/o router is utter simplicity: turn it on: done!
On the bright side, I have observed that for my particular Visible account, my hotspot speed ceiling is no longer 5Mbps (as it was for the first 4 months), but 10Mbps (down and up). This is a surprisingly impactful difference (and in a support chat this month, a Visible rep denied that their 5Mbps hotspot ceiling had been raised...).
Anecdote: earlier this month I had to spend a week in Phoenix, and most of that time was spent in a hotel, waiting, so I entertained myself (and checked on what I was waiting for online) using a Chromebook; I used my Visible hotspot for the entire 7 days' stay (poor hotel Wifi): it consistently delivered 10Mbps the entire time (many hours per day).
Obviously my ability to get 10Mbps from the hotspot is dependent on sufficient local cell network resource availability (and in my examples I'm admittedly NOT boondocking). Regarding Visible's unlimited data: this month (so far) my mobile data usage is 37GB (I think this is the most cell data I've used in a month) with no slowdown observed.
Another anecdote: last fall I spent 4 days at Grand Canyon's North Rim (Lodge); Visible speeds were amazing (best of the trip)! I'd be sitting on a bench overlooking the edge of the Grand Canyon, enjoying the amazing view while doing a multi-100MB download at extreme speed on my phone just because it was so amazing that I could (I couldn't help myself).
In summary, I have no reason to even think about quitting Visible; IMO it's an amazing deal, and liberating in the sense that I don't have to worry about how much data my phone is using; in fact, I leave my phone's WiFi turned off and use cell data exclusively at all times (including while at home). And I've received no reports of callers/texters being unable to reach me.
On the few occasions I've contacted Visible support, they've resolved whatever need I had, without significant delay.
For reference: my previous provider (for 6+ years) was Cricket, on a grandfathered "5 lines for $100/month" deal (4GB/mon NO hotspot). Eventually, only 2 of those lines were being used, so the low per line cost became irrelevant (and I resolved to never let myself get locked into a family plan again; the grandfathering effect led us to stick with Cricket far longer than we should have).
Aside: wanting a second voice+text line on a different cell network "just in case", I'm now on my 3rd month running a $5/month unlimited voice & text, 500MB/month Hello Mobile (T-Mobile MVNO) line. 500MB/month is a tiny amount of data, so this phone runs with WiFi enabled at all times (sometimes I'll use Visible hotspot with it) and with most apps blocked from using cell data to conserve. The service has worked fine for me so far (being a backup, I haven't used it heavily), and costs little more than "parking a number" at e.g. numberbarn ($2/month). Customer service is "bare bones", but I've only contacted them once (not for an actual problem). My only annoyance thus far is that (unlike Visible), they gave me no options regarding the phone number (including area code) associated with my new SIM. For that reason I did port in a number to my Hello Mobile line 3 weeks in, and that process was fast and trouble-free (same as Visible).
Previously on the same phone (Samsung Galaxy S9) I bought a TextNow (also T-Mobile MVNO) SIM to obtain its free unlimited voice+text service plan, however in practice I found TextNow annoying because it isn't real cell service, but instead its SIM delivered cell service only via an ad-laden TextNow app (which seemed to always be getting updated with new misfeatures). Also the rate of spam calls on my TextNow-assigned number was extremely high. In contrast, Hello Mobile gives me real cell service (can be used with any phone/text/app on the phone) on the TMO network for $5/month.