Yeah all that fancy Imperial armour had a bad design flaw, rocks thrown by teddy-bears! The original script had that is was to be Wookies not Ewoks, so we were to visit the Wookie home world rather than Endor, but Spielberg had been whispering in Lucas ear for a while about the merchandising aspect and targeting the children demographic etc, and there were some issue sourcing enough really tall people to play Wookies and costume concerns with that. So yeah, primal savage wookies (that could indeed have given the imperial troops a serious run for their money) became 'child bait' for future merchandising opportunities. The Ewoks don't upset me now as much as they did (in part because i've witnessed so much worse in all the prequels and the total fail in the New stuff), but it would have made Return of the Jedi a much better film if he had gone with Wookies.
Oh and as added punishment i've also forced myself to re-watch Revenge of the Sith (i watched Episode I in the cinema, and that scar was enough to never own it, and Attack of the Clones ended up in the bin after a few views) to get the full flavour of Lucas personal fall (and fail as film-maker and director) and next up is The Force Awakens to cement what i already know. I did get Rogue One on DVD, not that long ago (xmas iirc?), and it annoyed me enough that i just could not carry on despoiling Star Wars by watching it again (so soon!) on top of Revenge of the Sith and The Force Awakens.
RIP Star Wars, and thank the gods i actually have original versions of the original trilogy, so i have them 'untainted' by Lucas-as-fallen-director