you may find coil pikes weigh almost as much as your coil lyrik, mine certainly did!
In answer to your quiestion, air revs weigh much less than but share many spares with your pike. A bit less ‘built’ in the crown/steerer area than pikes but I find my mates 140mm air u-turn maxle rev almost indistinguishable in use from his old pike (coil) and my last 2 pikes (also both coil). Air u-turn is a bit more of a faff to service at home than dual air or coil, but you don’t hear the complaints on here like you did about the old 2-step air spring.
A mate has a coil lyrik on his huster and it is a truly hilarious bike to ride (in a really really good way 🙂 ). It even climbs ok with the fork at 160mm.
A hustler is a pretty burly and heavy frame, you will have to throw quite a bit of money at it to get it really light in weight, light fork or not. If it was mine I would keep the lyrik at 140mm except for longer downhills and just enjoy it whatever it weighs, you can always save a heap of weight in rims, tyres and tubes (or lack of) and keep the performance of your lyrik for fun bits. Bear in mind how much you will lose trying to sell your lyric and get a new fork.