We need a new razor, something along the lines of "do not attribute to FANG marketing what is better explained by misplaced expectations".
I think you overestimate some professional people's income (especially if it's sporadic) and underestimate their other expenses.
I've known many freelancers who buy a new laptop twice a decade at most. It will be the single most valuable object they own, and may be the result of saving for months and careful consideration of what to buy, intending it to use it for many years.
A spare good laptop "just in case" is not a realistic option for them.
Most of them could buy a second laptop if circumstances arise where it's absolutely necessary, but it would be hardship. So they wouldn't get one just as a "nice to have", a spare laptop lying around doing "nothing". Especially if it's going to be outdated by the time you have some use for it. Events where you need a spare device are quite rare after all.
That might be below "the basic cost" of running a sensible business, but for people on median and/or sporadic incomes it's a significant cost, only worth bearing if and when it becomes necessary.
I don’t mean to belittle anyone’s hardships, the stress of failing in particular. Being a "pro" is not amateur work.
Except for the obvious extreme scenarios, if your business collapses when your laptop fails, I think you are at fault, not Apple.
First, on Apple devices there are more software-induced failure modes than there had been in the past, and many of these failure modes are far more difficult or obscure to recover from. An OS update bricking your system in a way that Time Machine (or a disk image or similar) couldn't recover from was incredibly rare until rather recently.
Second, Apple devices have become so integrated and locked down it's now impossible to use some of the historical strategies to get yourself back up and running faster in the event of an unexpected failure. For example, you can no longer take the drive out of your current device and stick it in a replacement device to continue working. You've gotta make sure you have a perfectly working backup system to do that now, and even that takes waaay more time then the old-school drive swap. We're still not at the point where it's easy to shift your entire life from one machine to the next unless everything you do is cloud-based (which isn't the case for most).
Third, Apple's devices in particular have become harder to repair. They have more proprietary features than they did in the past, and a less friendly attitude towards repair than in the past. Apple don't release detailed documentation or repair manuals on how to e.g. revive the T2 chip, and AFAICT some of the tools needed to diagnose and repair Apple devices are internal only. It's now also impossible for all but an SMD repair shop to replace certain components if they fail because they are now soldered to the logic board. This, combined with the turnaround time for repairs on Apple products being ridiculous, has put even more pressure on people to have more robust backup plans than before, and penalises those without these plans moreso than in the past.
Forth, Apple's devices have become more expensive in the first place - or at least, there are now fewer options for folks to get the machines they need from third parties via upgrades. I typically work in smaller businesses and with freelancers and contractors, and many of these folk used to buy lower end models and upgrade the components over time as their needs improved and components got cheaper.
With soldered storage these days it can also be more difficult to find a suitable machine to buy e.g. used while you wait for your main machine to be repaired. Need a 1TB device? In the past, you could pick up any used machine on the market of approximately the specs you need, and simply swap in aftermarket storage. Now? Well, you're limited to the tiny portion of Macs originally sold with 1TB drives. There may be some way to use an external drive for this, but damned if I can find instructions on how to do so on Apple's website. What I can see however is a disclaimer that Macs with a T2 chip might be more difficult to use external startup disks with. I'm sure I could figure it out eventually, but I'm pretty sure your average freelancer would struggle.
So while ultimately yes, you as a professional can do things to mitigate the circumstances of any single point of failure and should do so where it makes sense, from where I sit this is an increasingly difficult and time consuming process. And all of that extra difficulty has been forced upon its customers by Apple.