Graphics aren't the reason games take 7 years, it's cause most developers fake work from home now and have no real or enforced deadlines. They went from pre-covid 40-60 hour work weeks with supervisors constantly hovering around their cubicle's and studios being shut down for missed milestones, to now rolling out of bed at noon and spending an hour fiddling with something, then quitting for the day. And the mega publishers largely let them continue to delay out to infinity cause they don't want Jason Schrier writing a hit piece about toxic work culture, crunch, or mass firings.
Metroid Prime 4 is an uprezed texture enhanced Switch 1 game (i.e. predominantly PS360 grade assets) that took 6 year for Retro's portion alone. The problem is zoomer and younger millennial post-covid work culture, not graphics.