https://www.pcgamer.com/after-16-years-of-work-hardcore-realism-mod-ghost-recon-heroes-unleashed-is-finally-finished/

Heroes Unleashed is a mod for the original Ghost Recon that promises to turn it into "the most hardcore military shooter simulation ever made." Developer Apex Mods began working on it in 2002 and now, in 2018, version 1.0 is finally ready to go. 

I haven't played the mod myself, so I can't comment on how successful it is in achieving its goals. But Apex Mods certainly sounds committed to the job. "The direction the series took after original Ghost Recon just saddens me, and that goes for all sequels, including the latest," he said in a Mod DB interview.