Of course. You'd be hard pressed to find a scenario on the web where selection bias doesn't come into play. Regardless, there's a level of distinction between "I had a bad experience" and "Paypal has inexplicably frozen my funds."

I agree that there are numerous positive experiences out there. I would imagine PayPal would struggle if there wasn't a large user base that was satisfied. The point here is that some people are starting to reassess and or question the net-benefit offered by PayPal at the cost of these inconveniences.