I have not seen TLR for years, so I must withhold my comment on the way Buckwheat was depicted. Yet, I do admit that blacks were usually depicted as superstitious, ignorant, & cowardly in those old films. It was comic relief when, for example, in a horror film, a black guy's eyes pop out, and he runs for the hills when the white guy even mentions the word 'zombie'; which word had a much different meaning then than now.
I must admit that I know little about Hal Roach's policies.