You may have got it the wrong way around!
This may be more about moving from POWER to x86 (and maybe back again later!). Let me explain. IBM have a massive AIX customer base who want to get off POWER onto more commodity x86 kit. In order to migrate there needs to be a critical mass of enterprise application stacks that run on BOTH the old (POWER+AIX) and new (x86+Linux) plus large 'migration projects'. The medium to long term revenue is in the giant projects to migrate and around software licensing and support contracts once everything has gone 'to the cloud'. When IBM are the largest supporter of the most commonly used operating systems in server land while offering a reasonable alternative to AWS (or stay on AWS if you must!) then this is a rather canny and strategic investment for them. Far less likely to have legs is IBM using their half a million internal users as beta testers for an enterprise-focused RHEL desktop distribution, challenge there is that IBM sold off the x86 hardware business to Lenovo and the Apple/Microsoft partnerships are not interested in alternatives to OSX and Windows.