Unfortunately I have no clue how to get a company to put money into the open source we use. Not just my current company, but any company. I've sometimes been able to get permission to contribute something I build on company time, but often what I really want is someone on the project to spend a year or two maintaining it. Do the boring effort of creating a release. Write that complex feature everyone (including me) wants.
In decades past companies you to pay for my license for Visual Studio (I think of a MSDN subscription), clear case, a dozen different issue/work trackers. However as soon as an open source alternative is used I don't know how to get the money that would have been spent to them.
Come to think of it I'm maintainer of a couple open source projects that I don't use anymore and I don't normally bother even looking at the project either. Either someone needs to pay me to continue maintaining it (remember I don't find them useful myself so I'm not doing it to scratch an itch), or someone needs to take them over from me - but given xz attacks I'm no longer sure how to hand maintenance over.