Yes it’s supposed to be off-putting, I get the point...it’s just done poorly and dumb lol. I would like to think they could’ve come up with a superior way to show the Symbiote having an effect on him than that. Also Topher Grace was totally miscast.
Spider-Man 3 would’ve been much better without Venom, Shoehorned in Gwen Stacy, etc. Sandman and New Goblin (especially New Goblin) likely would’ve gotten the time they needed to properly shine without Venom. Unfortunately we never got that film