Flaps 30 is good enough for a 7000ft rwy...its good enough for 6000ft even if its wet with good braking action....no sweat.
I guess that would depend on the braking that was used considering that at Flap 30 and MLW Auto brake 2 will pull you up in 2370m nil wind. The runway is shorter than that so AB2 is obviously out if you're silly enough to be using Flap 30. Try AB3 Flap 30, if you do everything perfectly as by the book with nil wind it will pull you up 370m short of the end. How many people chew up 370m by carrying speed into the flare or having a touchdown located further in than 1000 foot? Plenty. If you were AB3 and flap 30 and touched down at the 2000ft markers for whatever reason, you will have to intervene with some heavy braking to avoid an overrun.
What if it was a 3 kt tail instead of nil wind? That increases all the distances by about 100m. Nah, Flap 30 in this situation would be a poor choice if you had no wind and were heavy.
Even Flap 40 AB2 will stop you only 30m short of the grass at MLW and put you 70m off the end if you have a 3kt tailwind.
My point? This needed to be a Flap 40 landing with AB3 as a minimum which will stop the aircraft in 1700m if everything goes well, it leaves you with about 500m for unforseen things like
1/ not crossing the threshold at exactly 50'
2/ not being exactly on speed
3/ not executing the perfect flare and touchdown
4/ the reported nil wind actually being a slight tailwind.
For all I know this crew did use Flap 40 and appropriate braking, but to say that Flap 30 is 'no sweat' is to ignore variables that you have limited control over, and to bank on everything going as planned.
PS all the above figures are derived from my books and the aircraft they apply to have 'short field performance'. I don't know if the accident aircraft did as well.
At max landing weight the aircraft legally requires a strip length of 1620m dry or 1860m wet (nil wind, standard day etc). If it's not short field performance then it'l need a fraction more.