Is that really a flaw in RenPy's RNG or just normal RNG at work?but renpy RNG tends to get stuck generating towards one end of the range given randomly
When you're flipping a coin (which is essentially what's done here), it's not uncommon that you get the same result several times in a row. One time in math class we did 100 coin flips and having sequences of 4 to 6 times with the same result was practically normal.
Don't have a RenPy dev environment setup here, so I'd love to see someone sharing the result of executing the above code a couple thousand times or so.