Making your code useless to some of potential users is a useful feature?

I do not care if "potential user" is big corp that do not intend to contribute back. So yeah, it is a feature.

Still, how preventing said corp from using this software help you, or anyone else?

If you read between the lines, this is the very reason why Id released the source code as GPL instead of BSD: They didn't want their competitors to take their engine, make proprietary improvements, and deprive Id of revenue using their own work.

They never open-sourced any of their engines until after they had published a game with the next iteration of their engine.

Sure, but that just means they had multiple methods of ensuring they had created a suitable moat against competitors, the GPL being just one of them.

They didn't release any of this code as open-source until they'd wrung every dime of engine licensing out of it and it had been completely obsoleted.

It's free-as-in-couch software.

1) If I and said did not collaborate, then it will not help me, or anyone else.

2) If said corp refuse to collaborate with me and will use my code for free instead, then it will not help me, or anyone else, except said corp.

Why I should care about (2)?

Because - as it happens fairly frequently in BSD land - said corp might change their minds and contribute back, code and/or money.

Ok, when they change their minds they can start using GPL code with no issues.

Less time wasted on free support requests would be one way.

1) it helps their competitors

2) they may change their mind

3) they may pay for dual licensing (in case of work by a single author)

In general interests of unfriendly corporations and mine are more likely to be opposite than shared.

The answer is in the question.

Not really.

Yes, especially if the code not being GPL means the bad actor can create a product which then makes your code useless, or worse, evil (via a monopoly, bundled telemetry, or otherwise)

Can you show a scenario demonstrating how GPL prevents this from happening?

GPL prevents this from happening by requiring your competitor to open the code under the same license.

For example, Oracle tried to outcompete RedHat by cloning the RedHat Linux into Oracle Unbreakable Linux.

So, without GPL, how would Oracle render RedHat useless with telemetry? And why didn't it prevent the Audacity drama?

Without GPL Oracle could make closed source improvements which RedHat could not use, giving Oracle an edge over RedHat. If RedHat then went under because of that we were stuck with a closed source Linux.

The Audacity drama is solved by GPL, you can compile your own version without telemetry. Forks will pop up and the Audacity developers will backtrack and remove the offending parts of the code.

Ah, so it's really about making it harder for other players to improve their product?

As for Audacity - the exact same thing would have happened with any other Open Source license; GPL doesn't make it any easier.

>Ah, so it's really about making it harder for other players to improve their product?

No, it's about keeping those improvements open source.

>As for Audacity - the exact same thing would have happened with any other Open Source license; GPL doesn't make it any easier.

Yes, it does make it a lot easier since the Muse Group (assuming they don't own all copyright of Audacity, if they do the license doesn't indeed really matter) has to release all improvements as GPL and the fork can simply cherry-pick them. With a MIT/BSD style license they could just make it proprietary and then we would be stuck having to choose between an outdated Audacity and a non-free Audacity.

They can’t make it proprietary, because the developers would then go with the open fork. In this case GPL protects you from a scenario which cannot happen for other reasons.

But the improvements they make wouldn't be open source so the open source version would lack those features, which means we would be stuck having to choose between an outdated Audacity and a non-free Audacity.

Open Source developers would develop closed version instead of the open one? How?

Muse Group bought Audacity and are developing it now, their developers will use whatever license their employer tells them to use. They are the main developers of Audacity now. Any fork will have to compete with their work.

No, it’s just about getting compensation back for your work. If Oracle benefits from RedHat’s initial work then it is only fair that RedHat benefits from any improvements that Oracle later makes.

Assuming that Audacity does not have a CLA the GPL license will prevent muse from forking Audacity into a closed source project and continuing their development there instead. Instead they are required to keep any modifications open source, allowing users to remove aspects like the telemetry.

Erm, Oracle is literally selling repackaged RHEL; they don't need to contribute anything back to Red Hat. They would if they wanted to replace stuff with their own closed-source forks, but that would be completely unpractical for reasons not related to licensing (see how Oracle's closed source ZFS become irrelevant compared to the Open Source ZFS).

As for Audacity: its owners couldn't do that without closing their fork, which would mean splitting off with the developer community and becoming irrelevant.

> So, without GPL, how would Oracle render RedHat useless with telemetry?

I cannot understand your question.

> And why didn't it prevent the Audacity drama?

It does. See https://github.com/temporary-audacity/audacity

Here's a very recent example, the Audacity fork without all the new telemetry and related issues: https://github.com/tenacityteam/tenacity

I'd rather an end user not get my code at all than they get a frozen binary that they can never fix bugs in.