While plagarism is indeed a thing, I think that often times criticising a work of media for being too close to it's inspiration is quite ridiculous.
The literal highest grossing media franchise of all time was a spiriual successor, and quite a flagrant one at that, but nobody brings that up or cries plagarism - even though the similarities are just as major as they are between say, Family Guy and The Simpsons or Chuggington and Thomas the Tank Engine - different executions of an extremely simple basic concept (an average if dysfunctional nuclear family gets into suburban antics with a large supporting cast, living trains work together in a railway and learn the power of teamwork, a mere child overcomes the odds and becomes a legendary hero with his friends while fighting wacky monsters)
It is undeniable that there's a lot of media made to cash in on another's popularity: Rainbow Butterfly Unicorn Kitty to Unikitty, Schnookums and Meat to Ren and Stimpy, Discovery to Minecraft, Ratatoing to Ratatouille - but usually those rely on branding more than the actual product to become popular. Generally looking at branding side by sode is a good way to tell if something is really a rip-off. Logo typefaces, character poses, titles, so on.
I guess you could say that Crash Bandicoot isn't "true" 3D, as it has a fixed camera and really only focuses on forward and backward, essentially making it 2-D game but flipped 90°.
But the formula was good enough to make Crash 4 feel huge despite having a fixed camera.