or in support contracts more accurately, which would disappear if others would bring ability to support those (by access to same source code and ability to fix bugs)
and that means desktop devices, not servers, embedded or smartphones: not overall shares.
common error is picking one slice of the share and claiming it as something else.
the big three have been Lenovo, HP and Dell for a long time, order of those has switched sometimes. so depending how you slice the share, you could find a niche where somehow it would appear as whatever you want it to be, usual thing when reporting market shares: "we are top in this is super-niche slice of the overall market"
looking at filenames in top one there's a bunch of built dlls and exes there which looks like it is just installation of built code instead of source..