Shoe size doesn’t make any difference in terms of the angle of your foot - at least not with the better makes of shoes and boots. When they market a model of shoe as having, say, 4” heels, that will be the base line height for a base line size, say, a size 6. As the sizes go up or down the physical height of the heel will vary so that the lines and proportions are identical right across the range of heights.
A size 7 would have a 4.2” heel and a size 8 maybe 4.4” but they would still be sold as 4” heels as that is the standard for that particular line. A size 5 might have a 3.8” heel but would be sold as a 4” heel. It’s all about consistency and keeping the same proportions.
Italian heels even has a chart on their website giving the exact heel heights for 100mm and 120mm heels each shoe size. I have a pair of their 120mm stiletto boots. In my size the heels are actually 147mm to keep the correct proportions. I think in their case the heel heights are based in a size 38 as standard.
Other makers do the same. So having a bigger size does not change anything. Neither does having a smaller size. They keep all the proportions and angles the same