Alright. So yes it was hit by the number squish true, and maybe that was the only thing done to it. Obviously it should be reduced since the health pools were reduced as well. But relatively speaking it is still far 'worse' now than it used to be. Or well, it used to be utter crap doing barely anything at all in vanilla until somewhere around legion as far as I remember
this is its original form. Pretty bad right? even in vanilla this was bad.
Alright, so I remember I found it while on a ptr with its tooltip saying 5,6-5,8k dmg (as far as I remember) at the unscaled pre-bfa version i.e. lvl 48 item lvl 53. With low to no versa. It was even more OP for fury warriors then as battle cry gave you a 100% crit chance on all attacks which included rammstein's that ensured you a 7-8k hit in pvp which was almost a oneshot of twinks. I played 50 twinks at that time but their health pool isn't and wasn't insanely different from 49 twinks, also most 50 twinks at that time used any gear "of agility" etc. they just loved being glasscannons. So a glasscannon lvl 50 twink had about 6-7k hp. A balanced gear lvl 50 twink had 8-9k and a balanced-staminafocused had 10k-10,5k hp. So that means even a non crit and without any dmg increases as versatility or tiger's fury (15%) etc. it would surely do MORE than 50% of the targets hp.
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Now it does around 1,5k dmg scaled to lvl 59 with roughly 4% versatility. Most lvl 59 twinks have around 6-6,5k hp. 1,5/6*100=25% is the dmg of the full hp it does now at lvl 59, which is rather acceptable for a semi-long cd trinket, that takes up a trinket slot, and also has a slight warning-delay when used to allow instantaneous defensive cooldowns to be pressed. Besides tunneling below 30% hp is never recommended. We know that from the execute range for example, which is even 35% now with the massacre talent on arms warriors that I fear even more as it is instant and spammable. Also it seems that the Ramstein's trinket has it's aoe nerfed in bg's at least, can anyone confirm that? I recall checking combat logs after using it on multiple targets in a bg and saw that only one of the hits dealt full damage whereas the remaining aoe hits were all the way down to 500-600 per hit. (and I doubt they all randomly had a big defensive cd up with a similar big reduction). Now on my lvl 50 (similar in gear and dmg and stats to 49 now, only like 1 stat difference as it is now) rammstein's does about 1330 dmg with about 8% versatility. So if we assume the average (non-glasscannon(i.e. core items with 0 stamina etc.) have around 4k hp. It adds up to about 1/3 of the targets hp. Which definitely I agree is too much, it shouldn't be over 30% for sure, but even at the 25% which it is around at 59 I never felt it being any issues and I often find it better to use other trinkets instead for many situations. My consolation for 49s having a hard time with this trinket is to keep a healthy health pool, don't sacrifice big pools of stamina on gear for a bit more damage. Try to stay above 4k hp unbuffed at least.
My verdict on this is that it is still a cool 'tool' trinket that doesn't have to be nerfed into uselessness but tuning it slightly more in the 40-49 bracket to about 1k dmg down from about 1,3k so it is only around 20% of targets hp (that join a bg prepared gearwise obviously) might be a good spot to have it in. Or keep it as it is but make it so it is no longer able to crit nor scales with versatility which is usually what can really make it feel dangerous. Else keep your hp high and save defensive cds for bolts.
I hope my wall of text if you got through it could help console on this matter, just a bit at least.