I think a year ago player "ribbon M" of raids still ended somewhere in the 20000-50000 range, but now that has been sliced down to 5000 (was 8000 a few raids ago IIRC).
Together with the tweaking of the milestones and (boss power/stats), I guess this means Gree has split the raid players into 3 categories. (following numbers assume they keep cycling the milestones through the 5 mono-element shadowforged fragments at a constant rate and assumes no fragments from other sources than 2-day raids)

- The very big spenders that can get up to 11 shadowforged fragments from milestones, probably 1 fragment from player rank and of course the player and probably guild dragonforged armors. If they finish all milestones each raid, they could craft a set of 5 shadowforged after about 2 - 2 1/2 months.

- the people doing a guild dragonforged run that I guess get about 2-5 shadowforged fragments as sideeffect of their run plus the guild dragonforged armor.

- the rest of us that don't gem or only gem a bit on the raid to whom Gree kind of signaled we are not worthy of a ranking (by slicing away the majority of the player ranks) and should instead purely focus on the milestones by placing that 2 shadowforged fragment bait at the 5.2M goal there. If you consistently get those fragments and the fragment rotation stays consistent over the 5 mono-element shadowforgeds, you'd be able to craft the first on the 51th week since the start of those milestones (you'd have 10 fragments of each on the 49th week), then the rest on the 53th, 55th, 57th and 59th week. So in a year and a bit less than 2 months, a patient player would collect the first 5 shadowforged through raid milestones. (of course by that time Gree will have released a rarity above shadowforged...)

Rewards wise, if you're not doing a guild dragonforged run, you're probably much better off in a guild that calls up level 2 and 3 bosses than anything higher.
(as a player mostly using epic+, I'm getting probably 30-40% more milestone points on a "legendary" lvl 2 boss than I get on a non-legendary lvl 3. 2 such players hitting it at the same time should kill it without wasting milestone points.)