Not quite that simple.
M.2 NVMe 1000-3500 MB/s > ~500 MB/s SATA III SSD > ~150-200 MB/s 3.5" SATA HDD > ~80-120 MB/s 2.5" SATA HDD
There's a range of performance when it comes to NVMe and typically, the 1-3.5GB/s are just burst speeds. You can find NVMe drives with good burst performance (great for OS and apps) that are worse than SATA3 drives when it comes to sequential.
Running apps, video editing, dealing with a bunch of small files, etc, yep absolutely go with a good SSD.
For static storage of MKV rips, etc., HDDs still offer better $/GB plus recovery is easier.
SSDs can lose charge and data recovery is more difficult if not impossible. I'd still trust HDDs more for storage/backup of large static data. For video playback/streaming (4K tops at what, 150Mbps or 19MB/s?), HDDs are more than fast enough.
There are 2 presumptions here:
1) MKV/video rips would be stored by most users on some sort of networked storage - NAS or a shared drive.
It would be unusual for someone to use a large USB spin drive attached directly to an ultrabook for mass video playback.
Even if no NAS, very few people would like to carry around a 2 or 4TBs of videos with them while travelling and it is reasonable to presume that most such users would already have a couple or more such legacy drives with them already
2) Majority of users in need of storage above 512GB on a local drive would need it for something that would benefit from high speed access - could be 4k videos for editing , or really large document sets or large image collections / image archives
With 1 and 2, safe to say that barring a few odd case, a spin drive with an ultraportable is not exactly advisable.
Coming to SSDs , any decent nvme will be considerably faster than a Sata SSD in almost every scenario - burst or sequential.
The only bottleneck with a nvme would be the (assumed usage of ) USB 3.1 bus as TB enclosures are still pretty expensive.
But even with USB 3.1, the performance of nvme will be better than sata in practically all scenarios.
Just that With the nvme, you would be saturating the USB bus while with SATA the bottleneck would typically be the drive itself
Considering the price diff between SATA and a decent nvme (970 Evo or A2000 if you want something slightly cheaper) is very small now , A nvme with a USB enclosure (or TB if price is not a constraint) is the appropriate choice for the vast majority of folks looking for additional storage with a MBA/MBP