My Digitakt 2 is still in the post, but I’ve used the MKI Octatrack since 2015, and helped at least one Elektron certified trainer refine some online course material. I know the unit fairly well (though around here I suspect that quality is par for the course).
I think it really all comes down to how you use the OT, and the style you write.
Personally, I came up step writing individual hits in programs like Cubase VST, and old school sequencers (Roland MC-50MKII, anybody? Bloody nightmare). I feel more comfortable writing drum lines in an environment geared towards arranging individual hits, and while the OT can do that with various inefficiencies (sequenced sample chains, or just loading a single hit to an entire track) it’s clearly geared more towards loops.
I think the Digitakt 2 is a useful accompaniment to my Octatrack as a generator of loop lines that can then be extended by OT resampling. The OT offers the ability to extend the Digitakt in both master FX options, and live set transitional opportunities. The Digitakt is also teasing potentially intriguing innovations I suspect Elektron is currently working towards; Cuckoos seems to suspect this is a soft launch for a whole new era of Elektron releases, both in terms of upcoming product reveals, and updates for the Digitakt 2. Below is a link to more on his reasoning.
In the end, I long ago stopped ranking Elektron boxes in tiered hierarchies - they ALL offer something unique which is lacking on the other boxes. Similar ideas implemented in slightly different ways (and this even extends to those very toy-like Model boxes). I passed on the original Digitakt thinking it a toy compared to my OT, but in the end that was just misplaced hubris (as such always seems to be).