You sully Carver's name; he rose from poverty. Yes, historians like DuBois, educators like Booker T. Washington, and many, many others also were great. Greatest scientist remains Carver in my eyes.
Carver was great, but wasn't he primarily in agriculture? Seems to me that Ben Franklin did much more to change the world in his time. lets see,
he invented bi focals, the flexible catheter, invented the lightning rod which actually saved lives, invented the franklin stove which gave out superior heat in freezing winters which also saved lives, was the first to note that electricity had a positive and a negative, invented swim fins, he observed the effects of lead poisoning, He also founded or co- founded the first public library where you could check out books, the nations first fire department, Americas first art academy, America's first public hospital. like Carver, he did not patent anything but let it be used freely by the public. He invented a clock that used a simplified form of only three gears, he studied the theories of heat transfer, and ocean temperatures. I think for his time he was much more diverse in his curiosity of invention. Of course they lived in different time periods and the methods of study had changed some by the time Carver was around.
Carver may have been the most influential in agriculture I think .He did things that revolutionized that area