Microsoft has a market cap of $2.8 Trillion.
IBM is only at $146 Billion. But IBM still has a higher head count.
You'd have to be blind to consider Red Hat not influential in its sphere.
While Microsoft makes $73B profit, IBM makes $2B profit.
Microsoft is in the group of "big five" tech companies (Google, Amazon, Apple, Meta, and Microsoft). IBM is not in that group.
The reason for that is IBM is significantly smaller in terms of revenue and market cap and so on. IBM exists in a tier below the "big tech" level. This is how company sizes are measured.
Very simple. Not complicated.
Server operating systems are a small fraction of Microsoft's business.
i.e. since they're older they're bigger
keep in mind that IBM[0] is over a hundred years old, and microsoft isn't even half of that [0]
[0] wikipedia
it would merely settle "for now" becuase as soon as either of them get succeded you will have to repeat the contest