I've probably posted a hundred messages here on MCAS! Most were downvoted to hell. The actual 737 pilots I talked to agreed with me, nobody else did. Classic Gell-Mann Effect. The only truthful account of the crashes is the official NTSB report.
The 737 is an electric drive, with a manual backup. The 757 is a scaled down version of the 747's dual hydraulic drive, no manual backup.
More efficient wings and engines obsoleted the 757.
Oh I was an aeronautical engineer (BS, MS aerospace engineering, concentration in fluid mechanics) for 8 years. Any pithy explanation of aircraft flight/engineering concepts that I post gets downvoted or ignored. Better yet, sometimes a java programmer tries to mansplain it to me in a worse way.
When I talk to airplane crews, their faces say "oh crap, another nut I have to be nice to". So I let slip into the conversation things only insiders would know, and they then relax and open up.
The 737 is an electric drive, with a manual backup. The 757 is a scaled down version of the 747's dual hydraulic drive, no manual backup.
More efficient wings and engines obsoleted the 757.