My take on pedal kickback is it varies a lot bike-to-bike, and depends on bike setup too.
I got a lot of it on my Ripmo(s), but they're a high anti-squat bike and I was running a Project321 rear hub with 216 POE, 30t chainring (Ibis recommends a 32t), and 11-50t cassette. Pretty much a worst case scenario. Like
@The Duckmeister says, it was worst when climbing. I'd be winching away in granny gear, clamber up onto a square edge and next second the cranks are trying to rotate themselves backwards (with some considerable force at times). If you tried to fight it before momentum had started moving the wheel in an upwards trajectory and onto the obstacle a little it felt like the suspension was suddenly locked out solely due to the rapid rise in chainforce. I did occasionally find I cop it on "descents" as well but generally just where I'd have been on a slight climb or flattish section of trail in a middle gear that dropped into a tight/awkward/slow rock section where the speed was low and rocks were in multiples. In anything but the heaviest gears (which I typically didn't have time to get into if it was after a pinchy or sustained climb) pedals would feel like they would try and kick my feet off. This is something the Pinkbike article just glosses over completely and reverts to the standard "pedal kickback isn't real" premise that everyone only descends in the heaviest gear available, and there's no slow speed drops/chutes/rock gardens/janky hairpins/etc... and even if there is we're all taking them at 20+ kilometers an hour.
More recently I've been enjoying both the Sentinel (30t & 10-51t) and Carbonda (32t & 10-51t) with their Horst & linkage driven single pivot (I think?) suspension layouts. They are much mellower in comparison to the Ripmo(s). Both have 'adequate' anti-squat to prevent wallowing, but predominantly rely on spring force and linkage progression to provide pedaling support - rather than relying on anti squat and chain tension to try and extend the suspension artificially to build a pedaling 'platform'. While these bikes are setup with hubs with low
er POE (72 and 44 respectively), neither are
low POE hubs regardless and I'm still yet to notice any PK issues.