Why? Is there something the current hardware can't do or isn't doing?
A total change of hardware makes the A2 obsolete and backwards compatibility becomes an issue. They'd be right back to the A1 vs A2 debacle with loads of ticked off customers.
Imagine buying the A2 a month ago, A3 comes out and then they release Trident V2 but only A3 customers can use it. They just lost a ton of customers. Neptune wanted backwards compatibility to be a main priority. You can't do that if you change the internals. If Neptune was being Apple, they would have removed ports, stopped supporting the A1 and A2, and forced you into a subscription model of some kind all while raising the price. I'm pretty darn happy they didn't follow Apple in any way here.
I mean you can look at GHL and Hydros. Neither are faster, better, or have more features in the end. Both have terrible software IME.