This is related to the fact that a lot of skills are basically trash & PCs don't have the budget for trash skills. Perception is almost always going to be useful to some degree. How often have you seen entire campaigns run without ever having someone use medicine/nature/handle animal history or performane? Out of the times those skills even come up in a campaign are they regularly important to any degree? Sure bob might tame a wild animal or use handle animal with a horse but was a possible failure going to have much more impact than "ok.. moving on" or something in even half of those cases?
Sorry just had to chime in here, many pages later. Literally in my last campaign session, the various PCs had to make Animal Handling (the ex-marine driving the horse-and-wagon cross country with the Exhasuted spellcasters in back because of a Forced March, ahead of a giant warparty), Medicine and Nature checks (identifying damaged plant life, determining they were medicinal plants picked clean, by said giant warparty, and understanding the medicinal salves would last only 3 days, giving a range of potential targets), Nature checks again (to determine that the awfully-conveniently-timed fierce storm was in fact
natural in origin (helped by a druidcraft cantrip), and not a big "we're hitting this location here" sign), and a performance check with animal handling (to calm the storm-spooked horses of the giants' target, so they could mount up and flee). Oh, and a
gratuitous Performance check by the bard, because why not!
Also used were Persuasion, raw Charisma, ranger Primeval Awareness (shocker, right?), Favored enemy, Favored Terrain, Survival (tracking, foraging), raw CON (the forced marches), Athletics (climbing mountainous terrain for a better view), Stealth (because giants!), and several raw INT checks (to recall previously learned/noticed information), and an INT/Arcana check (by the
warlock) to understand a weird floating crystal near the giants' target. [No combat... but that's coming next session!]
Otherwise, to the OP, I work hard as a DM to make the line between Perception and Investigation very clear. That being said, the vast majority of my characters will have moderate to good Perception skills - sometimes
despite low WIS - because nearly every bad situation starts with "make a Perception check"!! I won't let players "search" with Perception, but knowing this is a good time to Investigate is still valuable.