I should amend myself a bit here. I just saw a YouTube video from Rick Beato that got served to my timeline (gotta love that algorithm that knows anything I've spoken about today). It appears the crux of the similarity is in the slow, sparse piano part that features in the "groove" if not the melody of each song. The duh, DUH, duh duh. The chords are a bit different, but the progressions do sound very similar. So I was wrong about the extent of the allegations of what was "copied." It's a bit more substantial that what I understood it to be, although I'd also say that it's almost impossible that type of progression was unique to Let's Get It On in 1974. Again, I agree with Beato in that I think there are certainly more similarities here than what I heard in Blurred Lines to Got to Give It Up. In a sane statutory scheme, maybe we allow this kind of infringement analysis and then just use the damages analysis to let jury's conclude that the amount copied was modest enough to only support nominal damages. Unfortunately, the Copyright Act has a statutory damages clause assigning $150,000 of damages for EACH unauthorized copy, which again, is orders of magnitude over the license fee Sheeran would pay for just recording a faithful cover of Let's Get It On. It's all so gloriously stupid.
Link to the YouTube video