Maybe the people who did the theming stuff aren't the ones that would working on compatibility issues.

Thats usually the case in company driven projects but not necessarily in community driven open source projects.

If you would be the project lead and a person comes to you and tells you that he would like to create a newer modern theme. If you tell him/her no and that he/she should work on something completely different i wouldn't be surprised if you would never see him/her again.