That is right. I just know, that many companies flee from GPL licenses (and more so AGPL). They omit any product involving GPL just to be sure not to get any juristic hassles (if rational or not).

Here is the culprit: When no other people invest in enhancements, there is also nothing that can go back upstream.

I like free software very much, but I also don't want to be forced to give things free, that I make. Problem is not the small enhancements I make to an OSS product, but when I link or use some OSS part in a bigger software that I made -- should I always be forced to give everything for free?

Particularly for companies, that is a difficult thing.

To be clear: Of course I would give away my contributions to an OSS product, but I also want to be free, to use OSS in commercial products without need to fear that I loose my own rights.

GPL here is just difficult and when lawyers have to decide about software, anything can happen (as in the patent-wars).