This is despite predictions it would increase, and CO2 itself rising by 41ppm globally during the same period.  In terms of total emissions released by humans since the stone age, it's been a bonanza — in this 20 year period we emitted 38% of all the emissions we ever emitted.

So humans put out 656,000 Mt of CO2 and there's been either a decline or no trend at all in rainfall intensity.

Is 38% of all human CO2 emissions enough of a test? The satellites cover all the Earth, including the oceans which the met bureau gauges don't.

Thanks to Kenneth Richards at NoTricksZone for finding this paper:

New Study: 21st Century Precipitation Trends Have Become Less Intense Globally

Hydrological processes were expected to intensify with warming. The opposite has happened.

Per a new study, global precipitation intensity, measured in mm/hour per century, has exhibited flat (large precipitation systems) to declining (medium and small systems) trends from 2001 to 2020.

Nearly every which way we look at it, across the year, on different continents in different seasons, rainfall intensity is not getting worse. Small and medium size "precipitation systems" (red and yellow) have reduced in intensity in summer and winter and all over the globe. More widespread systems (green) are a wash with some up and some down, and none of it in a pattern that climate models predicted.