100% agree. On my current and previous road bikes I eliminated the highest cog (12 to 13t on my previous 9-speed, and 11 to 12t on my current 11-speed) in favor of having an extra cog in the more useful part of the cassette's range.

With a 50t big ring up front at 13t I was spinning out at around 30-31mph (thats like 100-105rpm for me, which at my age and size counts as "spinning out"). With my current 12t highest gear and same front ring that now gets me to about 32mph or so. Since I only ever get this fast on a downhill, at most I lose out in a narrow range where my 11t groupmates are still pedaling like mad at 33 or 34mph and I've assumed my "escape velocity" tuck to just ride it out.

The OP did order a new cassette with a smaller low gear, which is useful, but it probably would have been even more useful to skip the 11t as well. His original gearings had those horrific 3t jumps between each gear, and even on a smaller middle ring than I'm used to that's still very disruptive. Getting to 1t and 2t shifts would help him out much more than preserving his top-end speed while bombing down a hill.