Britney's was risky because of the video
Beyonce was because she had a pop sound before any other pop girl
Madonna's was risky because she was white and had a "black" sound so if people initially knew she was white, she would've flopped.

Ur So Gay risk failed, she got backlash and ended up scrapping that single all together

Just because of the video? Then it's not riskier than Katy.

Having a pop sound before any other pop girl? Ever heard of Britney Spears? Absolutely not a risk at all.

The Madonna one doesn't make sense to me There was a music video for it that she was in, she's clearly white... the label may have originally meant to leave it ambiguous but that didn't last long and the song didn't suffer when people found out she was white.

Ur So Gay was only ever a promo single. It wasn't meant to be her real debut single.

Yes it was risky. To the point where very few people in her label supported IKAG. She would've likely been dropped if it wasn't for those small supporters. At the time radio were scared to play it, and ironically, the first station to play it was in "the Bible Belt" area of the US.