It's conceivably part of the reason.

Earlier reporting on Windows MAU noted "400 million Windows PCs vanished in 3 years" (https://www.zdnet.com/article/400-million-windows-pcs-vanish... ). As Windows 11 wrecks havoc on older PCs, many may just sit unused or get discarded, thereby increasing the relative share of the surviving PCs (including Linux PCs).