I play him myself nearly exclusivly. While it is true, that Demavend himself became a lot less stronger, due to a single charge loosing value, engines are now a lot more likely to stick and more engines can use charges directly, which counteracts that. A couple of needed nerfs to NR swarm and Demavend should be really good again.
I have been playing NR almost exclusively lately and i've tried several archetypes, including charges.
Although charges works similarly to before, maybe even a bit better, it's still weak compared to other NR new archetypes like boost Meves and Foltest commandos.
Honestly the best card i found on a charge deck is the new Hubbert. The new Foltest Pride is also nice since it has Zeal and its harder to remove, but you need to have adjacent soldiers to make it do 2 damage, otherwise its just like other machines.
But the crazy points that the old Foltest Pride and Kiyan were able to do, that made charge decks the deadliest if left unchecked, yeah i guess those are gone.
Uhm, Demavend was never played (much) to begin with. The NR update changed little in that regard. Only the risky all-in cards, like Foltest's Pride and Kiyan, could have made a difference in the off chance they didn't get countered.
What I really wonder about is, if Demavend is still the best charge leader. Meve might work even better. Combine her with Priscilla and you get 2 additional charges instantly. And on average you can use Meve 1 turn earlier each round compared to Demavend which is huge.
Even Calanthe playing an Aretuza Adept and drawing Priscilla should be better than Demavend.
Maybe Demavend should give 2 charges every 3 turns, or get old Odos passive, giving each unit on play a Charge.