Don't think money is really the issue. Tesla lost more than GM paid for Cruise IN THE LAST QUARTER. For Tesla the problem is Musk decided that it was possible to do autonomy with cameras, which is way cheaper than using lidar and mapping. Would be fantastic if it worked. However, it hasn't worked out -- turns out cameras alone are not sufficient -- but Musk is now committed to being right. As a consequence it lost its connection to Mobileye, setting back AP, and hasn't been able to keep top engineering talent on the autonomy side. So more a case of "not invented here" than anything, an affliction which GM has been known to have as well (though obviously less lately).
Note that Tesla is at least in the game. It has an electric program -- Duh -- and it has an autonomy program.