Liam Neeson & Denzel Washington are pushing it past the point of believability imho. Tom Cruise & Keanu Reeves are at the end, as I see it, but in all those cases, a lot of the action is hand to hand, & that's what's hard to buy. Linda's Sarah Connor is just a gun toting badass. Charles Bronson pulled that shit off until he was in his 70s lol, because it isn't entirely unrealistic. Old people can operate guns.
I think what pisses me off about the entire Terminator franchise, since T2, is that, regardless of how implausible it might be to do it, the series has lost a great deal of it's top notch acting ever since it hasn't had Michael Biehn. He's the only missing element from that original recipe. It pisses me off that we don't see him more in major motion pictures in general. He's terrific. He & Linda are what MADE that movie something people took to. By all rights, it is otherwise a rather cheesy 80s B movie, & had you put it in the hands of any other unknown actors of that time, it most likely stinks up the screen. His presence is sorely missed imho. The casting of that original is OUTSTANDING.