First, if you're running it on an 8-core server, that's $16k per year, which is about what many companies are paying for an enterprise support contract. It's not much when you consider that it gives you access to Akka engineers at the cost of 1/10 of an FTE.
Second, the $2k number is a list price. All large enterprise deals are negotiated, and nearly all are discounted from the list price. Akka probably won't discount small deals, but they'll be forced to discount larger ones if the buyer has an alternative. Plus, the buyer will demand SLAs, dedicated support, and will often demand changes to the license and custom work on the software itself (tweaks to make it work with X, etc.)
Akka and their larger customers will make it work. The purpose of this license change is to give Akka the ability to get their customers to the table in the first place.