You're misunderstanding Intel's specs. If you want the chip to run within TDP you can only expect the base frequency across all cores, not the ridiculous turbo frequency. The best laptop chip Intel has right now is the i9-10980HK with 8 cores at a 2.4GHz base frequency and a 45W TDP. Apple's laptops are more than capable of dissipating the rated TDP and hitting the base frequencies (and often quite a bit higher), although the fans can be a bit loud. So Apple's designs are not broken, at least not by Intel's definition.
You can relax the power limits and try to clock it closer to the 5.3GHz turbo frequency. But how much power do you need? I can't find numbers specifically for the i9-10980HK, but it seems like the desktop i9-9900K needs over 160 watts [1] to hit a mere 4.7GHz across all cores, measured at the CPU package (ie. not including VRM losses). Overall system power would be in excess of 200 watts, perhaps 300 watts with a GPU. Good luck cooling that in a laptop unless it's 2 inches thick or has fans that sound like a jet engine.
It's not that bad - Samsung and Intel are at most 1-2 years behind TSMC. An eternity in terms of product cycles for sure, but society would not fall apart if Apple had to redesign their A15 and M2 chips for Samsung 5nm next year.
I'm not sure where everyone gets the idea that Intel charges a big premium for ECC platforms. If you buy the low-end workstation Xeons the processor costs about the same. For example, Xeon W-1290 (10C, 5.2GHz turbo) has a $494 MSRP. The i9-10850K (also 10C, 5.2GHz turbo) has a $453 MSRP. You also have to buy a motherboard with a workstation chipset to use the Xeon, but W480 chipset motherboards are also priced about the same (~$200) as their consumer Z490 counterparts.
The real reason ECC is not common is because it is perceived as unnecessary for desktop workloads. Software crashes and corrupts data all the time because of bugs, not bitflips. Most consumers care so little about their data that a single hard drive crash will wipe it all out anyways. Why spend 12% extra on memory if consumers hardly see any value from it?
All of the reasons you said are correct, but I want to point out that Windows on ARM is also a bad technical product. The Qualcomm SoCs in devices like the Surface Pro X are more efficient than Intel chips, but they are much slower for everyday tasks even on native ARM-compiled code. Emulated x86 code is even worse, as the slow cores are further held back by Microsoft's emulator implementation. Users may like better battery life, but they also despise waiting for their computer.
Apple Silicon does not make any of these tradeoffs. ARM code screams on the M1, and even emulated x86 code runs with comparable performance to the Intel Macbooks. Battery life is better across every workload. To the user, selecting the M1 over the Intel chip is a no-brainer (except for some edge cases like 32GB+ of RAM, where Apple has largely left the older products in place). This is the same playbook that made the PPC -> x86 transition successful as well.
Really, I find that surprising. I use a GTX 1070 and it's still capable of playing a decent number of recent games at 4K with the settings turned down. Seems like the GTX 1050 Ti should still cut it for some moderate 1080p gaming.
You can relax the power limits and try to clock it closer to the 5.3GHz turbo frequency. But how much power do you need? I can't find numbers specifically for the i9-10980HK, but it seems like the desktop i9-9900K needs over 160 watts [1] to hit a mere 4.7GHz across all cores, measured at the CPU package (ie. not including VRM losses). Overall system power would be in excess of 200 watts, perhaps 300 watts with a GPU. Good luck cooling that in a laptop unless it's 2 inches thick or has fans that sound like a jet engine.
[1] https://www.anandtech.com/show/13400/intel-9th-gen-core-i9-9...