I remember when I was in high school repping 130 lbs (when I started out) w/ a 7’ bar. I put collars on the inside and gave myself about 8" of usable bar space. I loaded it up to 130 lbs and tried benching it. The 130 lbs felt like 170 lbs. There was a major difference in distance though. Not a couple of inches.
I think deadlifitng is a little different since you aren’t trying to stabilize a muscle that is pushing.
It also depends on the rigidity of the bar. I have an ivanko PLing bar and its WHIPPY! I am used to it since its all I use, but the greater the distance that the plates sit from the middle, the harder the bar is to control.
With a bar, you can’t apply more force due to placement of the plates on the bar. Thickness of the bar would affect your biomechcanical leverages (pushing or pulling with an open palm vs closed, the open is MUCh moredifficult), but not the placement of plates w/ such a small distance difference. There is a difference, such as rotational torque (a smaller change in the angle causes the bar to move further due to the increased overall distance of the longer bar), but nothing that would really stop you to the point where your max is 100 lbs less than a “normal” set up.
At least this is how it appears to me.