I honestly found infantry to be really useful. If you're tactical and plan ahead, every map has multiple good routes to move infantry through cover and if you minimize exposure you can get close enough to enemies to scout them. They're also expendable so if you mess up, you can just use their (kinda bad) APC carrier to do the scouting instead, for the same reason. The extra movement speed of the recon platoon meant I pretty much always brought them instead of normal infantry, since they all die basically instantly and so I'd rather move faster to break line of sight faster as well as speed up the boring wait for the infantry to reach the enemy.
They aren't as good at scouting long sightlines, but are a lot better at scouting areas like factories or city blocks because they can just walk through 50% of the buildings. The trick I used was sending the squad out of a building just a little bit, seeing if they get shot at; if they don't, move into the street. If they still don't, move the tanks up. If they do, pause and move them not just inside the building but out of the back door to break sight and they usually survive. Sometimes I could even use this to bait enemy tanks to chase and they would drive straight into my pre-set firing line of tanks! (This method trivialized the final defense mission) The infantry pathing does need a lot of work though, they always get stuck whether I use automatic or manual pathing.
I do hope infantry does get better vision though, or maybe a directional vision one like tanks so they can scout in one direction farther. Maybe save it for a future "sniper team" squad that's great against infantry and hard to spot but really bad versus tanks. It's fine if we don't, though... It seems like the idea was that the terrible environment reduces visibility for everyone, so high-powered optics are A. hard to come by and B. really strong. It's nice having atmosphere affect gameplay for immersion.