That’s a massively blanket statement and how do you back that up?
20 years in the creative media industry tends to give you an idea
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A decade of that was with a production company that specialised in film and video. At the beginning we were fine with single CPU systems as our bread and butter was short corporate pieces outputted to VHS so we never had the time nor budget to push anything crazy, but as the work started ramping in length and complexity our investment in a couple of dual socket Pentium III workstations paid for itself very quickly.
By the time I left we were fully solid state recording, either holding all the rushes on central NAS with fibre channel connections or a massive RAID 0 on each system. 64GB RAM was minimum. A former colleague from those days just bought a couple of edit machines for his freelance business, all based around Rampage VI Extremes, NVMe RAID for his rushes source, all 4:4:4 4K RED footage, and 128GB RAM (he was advised against Threadripper). That's HEDT for you, couldn't do this on a mainstream platform.
Do we even know what extra features, if any, that the new AM4 chipset will offer? That alone might reduce the requirements to move up from AM4 for some.
ECC is already supported with some AM4 boards.
Granted, we don't know exactly what X570 will bring, but I can guarantee you it won't be to the same level as HEDT. Will be interesting to see how vendors make use of PCIe 4, which could lead the way to properly implementing multiple NVMe drives at full chat, and that will bring a Threadripper benefit down to the mainstream. But there's no way you're getting 128GB RAM on AM4, and only the super expensive boards will have things like 10Gb ethernet on them (by which time the board cost is pushing into Threadripper territory anyway).
I used to be a professional software developer and TR would have been complete overkill for me.
I've worked with many people who have used HEDT platforms for a fairly beefy server setup at a development level to bench scalability of their code before deploying live. It's also very useful to smash a bazillion VMs with every major permutation of your target OSes on a single physical machine. Hell, for years even my web stuff had to support back as far as IE6 and I sure as hell aren't having 10 dev boxes in my studio! Fire up multiple instances of Windows from XP and up across VMs and you still need a bit of grunt.
In your corner of the world you may disagree, in my corner of the world I fully stand by what I said: 16c/32t Ryzen will not even remotely impact on Threadripper.