That's a very good question because I didn't know that gassers (and presumably similar sized glows) could turn revs like that so it got me checking in to ring flutter. It turns out that ring flutter depends mostly on combustion leakage past the top ring and getting trapped by the second ring which can then lift the top ring off the piston groove which leaks even more pressure and power drops considerably. A fix is a larger ring gap on the lower ring (which reduces sealing anyway) or using a single compression ring. Either way, tolerances have to be kept very close but as engine size gets smaller the tolerances have to be even more precise because of scale. Ring tension (how hard it springs out against the liner) is also critical because if it's not enough then combustion pressure can force it away from the liner (especially if it's been lifted off the piston groove seat) and then obviously loses the seal. Too much tension causes high friction and wear. Once again, things like this are easier to control the bigger the ring is.

With smaller engines, all these problems with rings are overcome by using no rings, as with ABC, but there's a crossover point where ABC becomes a disadvantage. This is because ABC relies entirely on holding a correct piston/liner clearance with metals that expand close to the same amount but as the bore gets larger any slight difference in thermal expansion gets exaggerated. It appears the crossover point is at around a 1" bore which is about a .90 size engine. The largest ABC engine I know of is a 1.08 but mostly it's around the .90 size that you see some engines ABC and others as ringed.