From your link: "Although CO2 gets most of the attention, it accounts for less than half of this warming. Two-thirds come from non-CO2 forcings." So it's much over 5%.
All of transport sector emissions makes up 20%. The other subsectors are decarbonising, but there's no tech solution in sight for air travel in the needed timeframe. And air travel is growing alarmingly quickly (doubled between 2006 and 2019).
All the individual slices of the pie we can tackle are pretty small, aviation is one of the bigger ones. We can't keep subdividing and then concluding for each one that it's too small to matter.
That's true, but of course this is a much slower rate of improvement (30 years to 2x) than the growth of air travel, and has slowed in recent years[1] since seat density and seatu utilization can't be increased much more without radical approaches like sedating people and stacking them like cargo.
While the percentage shows that aviation is not a *priority* for climate change, the required reductions in CO2 emissions for the climate to stabilise are around 99.9%, so aviation-induced emissions will have to come down at some point.
Aviation accounts for about 2.5% of global CO² emissions.
https://ourworldindata.org/global-aviation-emissions
Rapidly ramping down fossil fuel based air travel will have approximately no effect on climate.