I'm not sure the Dev intent, but this is something people (generally high end raiders) have cited as a reason. Something about it being easier than correctly aligning the various different CDs in optimal ways.
It's a problem with the 2 min buffs.Is it a problem with the 2-minute buffs or is it a problem that the crit in this game is broken? The buffs have accentuated it, I don't question that, but the problem of damage variance given by the crit has always been there.
To give you a different way to think about it: If you drive down the road at 100 mph, is you driving at 100 mph a problem, or you driving at 100 mph in heavy traffic with lots of other people driving anywhere from 110 mph down to 70 mph all sharing the same road?
Without the 2 min buff issue, it wouldn't be the problem it is. Before the 2 min buff model, Crit was still the king of stats, but other stats could be respectable in various situations. The 2 min buff window blew that away because the value of getting a Crit under up to 47% boosted damage from aligned buffs is simply far and away better than any other stat, especially the sustained throughput stats like Det and (for Tanks) Tenacity. It also means the correct second choice stat is always Direct Hit, because like Crits, you want Direct Hits during that burst window.
The 2 min buff window heavily prioritizes bursty stats and devalues non-bursty ones, and means getting a Crit Direct Hit in a burst window can be a HUGE difference in your damage output vs not getting them in that window but getting them outside of it. You need something like 3-5 Crit/Direct Hits outside the burst window to equal your damage increase from getting a Crit Direct Hit in the buff window.
The problem absolutely exists because of the 2 min buff window. Even if it would still exist in a lesser form under the ShB 30/60/90/120/180 "consistently up" windows, the impact is outsized by combining all those buffs into effectively one superbuff every 2 minutes.