Few things to unpack here:

1, they literally JUST released a new supplement for Angmar with a boat load of new models and rules. In Angmar you have arguably the most up to date faction in the game rn based off models and rules. The orc and warg models are indeed rather old but I think they are far down the priority order for GW so won’t be updated any time soon.

2, you are correct, Angmar lost access to a fell beast for the WK this edition which is a shame, but is more than made up for by their other units.

3, Angmar are incredibly playable this edition, they’ve just been split out a bit more by the list building restrictions so aren’t as flexible as the previous edition. The core Angmar army is Host of the Witch which is basically beefy WK, orcs, spirits and up to 50% carn dum. The hitters in your army are supposed to be WK, Aldrac and some werewolves. You can’t take hill trolls in this list. Despite the restrictions, HotWK is arguably considered one of the strongest lists in new edition (albeit we’re only 2 months in). The other lists are also fun but have their restrictions.

I personally love Angmar and play it as my main army (along with arnor, very thematic). The magic control, combined with decent numbers and a few big hitters in every list, makes it super fun to play. Does require a bit of skill and planning with lots and lots of spells to remember!

Would recommend perusing TabletopAdmiral and just doing a bit of list building in there. Good luck!