B2B customers overwhelmingly would prefer to pay subscriptions instead of fixed up-front fees.Not necessarily. For example, none of my businesses use any software on a rental model where it is critical to our business and having it changed or switched off in the future could cause serious damage. Recent versions of several expensive professional applications we use have gone subscription-only, and our response is simply that we'll keep using the older versions and do without the latest features. If that ceases to be viable because we can't buy any new copies we need any more, we'll take our entire business elsewhere.
I have yet to encounter any software at any price in the business world where there really is no sensible alternative to paying an arbitrarily high price forever and for risking your business taking a big hit if the software gets turned off. And while sometimes compatibility and data formats can form a significant barrier, I have also yet to find any issue that truly could not be overcome or any customer, client or supplier we couldn't work with because they were using the latest and greatest version of something and we weren't (or vice versa).