Deno core is great and I didn't really abandon Deno – we support 5 runtimes actually, and Deno is the second most advanced one (https://github.com/openworkers/openworkers-runtime-deno). It broke a few weeks ago when I added the new bindings system and I haven't had time to fix it yet. Focused on shipping bindings fast with the V8 runtime. Will get back to Deno support soon.