An empty (olympic) bar is usually 20kg, or 20.4kg/45lbs if you live in poundland. Difficult to lift a lower weight than that if you go the barbell route.
Most girls at my gym lift more than just the empty bar for reps, even if they look new to the movement, so 17kg sounds like an underestimation for 1rm. When I first introduced my sister to the movement, she did 3x12 of an empty bar just fine.
I agree with you that 20kg for a woman is not thát crazy, even for a beginner. But the "woman's bar" is also very popular, which is only 15kg. I think the main reason many women prefer this one is because the thinner bar is easier to grip.
For a woman, 29.5kg is heavy judging by what I usually see when training. My gym has olympic bars, which weights 20kg. Rarely women add any more weight, some add 5kg each side and like 1/50 (made of my head) put 10kg each side. To go past novice level, you need to bulk and build muscle/strength. Women aren't interested in doing that for the upper body.
I am mid-50s, female, casual lifter, mostly do yoga & only lift once a week on average. Look lean but not at all bulky. I can bench 65lb, sure. Strength can be built separate from bulk. But personally wouldn't do it alone, just in case, and honestly it would be my heavy set. For scale - Big awkward dog food bag is 45lb and most of us can wrangle that, or a 50lb bag of dirt or whatever. So it's not a crazy heavy amount and also not crazy light.