call me old-fasahioned, but two spaces after a period will solve this problem if people insist on all-lower-case. this also helps distinguish between abbreviations such as st. martin's and the ends of sentences.
i'll bet that the linguistics experimentalists have metrics that quantify reading speed measurements as determined by eye tracking experiments, and can verify this.
You appear to be trolling for the sake of trolling, but for reference: reading speed is determined by familiarity with the style of the text. Diverging from whatever people are used to will make them slower.
There is no such thing as "two spaces" in HTML, so good luck with that.
Code point 160 followed by 32. In other words ` ` will do it.
edit: well I tried to give an example, but hn seems to replace it with regular space. Here's a copy paste version: https://unicode-explorer.com/c/3000
But...the vertical dimensions don't scale so well, at least in my browser. It causes a slight downward shift.
From what I recall, the size of a typical interword space is ⅓ of an em, and traditionally a bit more than this is inserted between sentences (but less than ⅔ of an em). The period itself introduces a fair amount of negative space, and only a skosh more is needed if any.
( or alternatively use nested sexp to delineate paragraphs, square brackets for parentheticals [( this turned out to be an utterly cursed idea, for the record )] )