But those Xeons were priced well beyond typical consumer offerings. The fact remains Intel kept those to 4 cores (adding only hyperthreading) for a period of about 9 years.
And as for the historical amnesia Intel dominated for over a decade prior to the arrival of the Zen architecture and during the latter stages of that period they took full advantage of that and were subsequently caught off guard.
HT was in the P4 in 2002, it's been 17+ years, almost twice what you state and nothing to do with the i series of chips, intel removed it from lower end variants, but that's not the issue here. Also intel weren't caught off guard, they gambled on being able to transition to 10nm and lost, that's why refresh after refresh has taken place recently. It just so happened that AMD was able to be competitive at the same time, not only on price, but on performance and supply. Zen2 looks set to move the goalposts completely if it moves to the rumoured 16c/32t top end as that's well into Xeon/TR territory. That's not ground intel wants to compete on, ever, as that's where the money is. Intel have history (x58/79/99) for dropping Xeon chipsets in consumer boards for HEDT and charging a premium, it didn't need to improve on 4c/8t for the masses - most of them have little to gain and those that do were a tiny percentage of the market - they were supposed to buy HEDT.
At face value your Xeon cost point is correct, but this is OCUK, so look a little deeper, the critical part of Xeon ownership for enthusiasts has always come down to 2 letters, the last was always an S, the first was either an E or a Q. With a little knowledge, 8C/16t CPU's were inexpensive for x99, in some cases you could buy the retail stepping for peanuts vs. the retail price, 24c/48t was possible. My 2630 v3 set-up (board, CPU, RAM) cost less than my Ryzen set-up, even with the latter enjoying some very significant discounts. Also remember OCUK sold x99 boards for as little as £99 new (Gigabyte EATX from memory).
Also no amnesia here, you seem to be assuming something I neither said nor implied - obviously intel were ahead for a significant period of time, obviously they resold the same processors with the same core count and minor IPC/clock improvements because they didn't need to innovate in the desktop market, it was so stupidly obvious that I wasn't aware it needed to be pointed out to anyone, you obviously do for some reason. However the balance has shifted multiple times over the years, many people either were oblivious to that or seemingly had forgotten. AMD gained a world record in clock speed for a microprocessor (still holds it iirc - 8+ Ghz), beat intel to single die multicore processors, hit 5Ghz at stock years before intel, set the standard in the mobile sector APU and even desktop APU's, pretty much took over the console gaming market, they also did quite well at GPU mining. So again, buy what's best for the task, if it's AMD then good for you, if your workload suits intel then great, but before making sweeping generalisations about either company, remember the history is long and not quite as clear cut as some of your points would suggest.