Note that I didn't say anything about air grabs, and I wouldn't say that DK's sideB is reliable for grabbing opponents. I as Kirby, always wait for my opponents to fall into my grab range/touch the floor/hit my shield and grab them while they're committed to the attack before grabbing them. Characters who are susceptible to juggling always airdodge into me and try to roll away, upB away, or attack me and try to knock me back, but they never footstool my shield, which most of the time would be a smarter move.