They're setting up for the forthcoming IPO.

I guess it's a classic move out of the IPO playbook at this point to gain content and users via third party clients and then turn around and eliminate them by killing their API access entirely and/or making it prohibitively expensive.

Seems like a weird move by someone who's been at Reddit since the beginning and presumably understands its users well to me though.

We'll see how it works out for them...