Isn't the Linux/GNU philosophy "Use the best tool for the job". Making OSS always a choice is good, but it is definitely not always the best tool for the job.
Even if it's not the best today the question is for tomorrow.
With proper funding you can hope open-source will become better and hopefully if more actors join the cost might even become lower.
Of-course you can continue to enrich the likes of Microsoft today because they are "better" but even not considering the cost with the current trends in Microsoft (and others) products you might still end-up with something worse and another expensive bill to pay to try to leave ...
“Best” isn’t a simple objective trait. Is that the one which lets you get your job done for the lowest cost? Or the one with the easiest training and documentation? The most consistent UI so you don’t have to retrain people? The one which avoids geopolitical concerns about ceding control to potentially hostile countries? Is it the one where you have the most control over the direction because e.g. there could be an Swiss digital service cranking out patches for things they would have to haggle with someone at Microsoft or Oracle to get implemented? What about the one which you can most easily fix accessibility problems with? (That last being a legal requirement doesn’t mean that certain companies don’t try to blow it off release after release)
Every one of those will have someone arguing that it should determine “best” status. A compromise like “usable and we have more control” seems quite defensible.
Sure, but if you let most people choose, they don't choose the best IT tool. They choose what they know. Or they choose the tool with the best marketing team.
Either way, you can't make a rule for people to choose the best tool for the job. A rule like this may come closer to the GNU Linux philosophy.
With proper funding you can hope open-source will become better and hopefully if more actors join the cost might even become lower.
Of-course you can continue to enrich the likes of Microsoft today because they are "better" but even not considering the cost with the current trends in Microsoft (and others) products you might still end-up with something worse and another expensive bill to pay to try to leave ...