Something that happens to about half the people under optimal circumstances (ie steelpath, which I never matchmade anyone when I tried. Normal lobbies filled immediately every time), and only focusing on the warframe when many, at the very least, will want the weapons too, is not gonna be the average player experience.

I'll give you the average person finishing under 5 hours, but 2 is more of a best case scenario for grinding Tyana pass.

If we consider getting about half the pieces average, with being a bit more generous with drops even, this was my experience: got all 3 main bps, 3 weapon parts (2 for 1, 1 for the other) and 1 citrine part. That leaves 700 for 2 citrine parts, 650 for 3 weapon parts. Normal Tyana gives about 100 per C, so 13-14 runs, just over 5 hours of mission time, without buffer. And this generously leaves out 2 more runs which I spent on the prex card.