It's not about money.
1.1 devs don't give a single fuck about being up to date. They do more important things such as optimising code and fixing bugs in sources. Nobody has time to look for networkmessages needed to connect, it's not that easy as you think. If it was, I'd do it myself.
- something changed in a client, it needs more data to connect now, but I don't know what needs to be added
- something was added to .dat file(rme suggest it's related to looktypes, but I'm not sure) so if you want to use otclient you have to consider these new bytes and add new client version to sources
There is a chance that otx devs did it already, but it may be buggy.