Western media always gets Tiananmen wrong. Bro who help up the tanks, for example, was trying to convince them to stay and oppress the student movement. The tanks were leaving on the second day. It's just so very exhausting.
Yes, they were leaving, this was after they had cleared the square, but I can’t find anything that indicates “tank man” was trying to get them to stay. He wasn’t blocking the from entering (people do get this wrong) but was chastising them for what they had done. At least, that’s my understanding,
Chinese state TV treated him like a protester, and spun it as an example of what nice guys the Chinese Army is:
CHINA TELEVISION ANNOUNCER: [subtitles] Anyone with common sense can see that if our tanks were determined to move on, this lone scoundrel could never have stopped them. This scene flies in the face of Western propaganda. It proves that our soldiers exercised the highest degree of restraint. https://www.pbs.org/wgbh/pages/frontline/tankman/etc/transcript.html
It’s not about motivation, it’s about flexibility and transparency in procurement, and additional stimulus to be more data-driven on each side, from operator to officer to government officials.
All photos have an exposure time; that's an inherent property of them (think film). Compositing images digitally on top one another is not an inherent property of photos.
You can double expose film, and I think that's a finer line, but I think the distinction most people care about is really analog vs digital.