I think that's an entirely different topic that what Apple is doing to strong-arm customers hopelessly locked into its hardware platform.
Hardware and software are linked. Can't have one without the other. In Apple's case, both platforms are a little bit more tightly integrated then others.
And there is vendor lock in with software.
I'll agree that Adobe has a monopoly of sorts.
Nothing illegal in this country about a monopoly directly. That's not what got MS back in the 90s and it's not what has Google in the bind right now. Not technically anyway.
None of them are bringing any kind of credible challenge to Adobe.
Oddly enough those that did or maybe had some features better then Adobe counterparts were gobbled up and killed off by Adobe. And they leave the rest floundering around so that way people have choice. Which is the key thing.
The advertising industry circulates mostly Adobe-centric files. It's not about anything "open source."
Amazingly, I stayed away from Open Source this entire conversation. I talked about Mac, Windows and Hackintosh. Nothing about Open Source. Now, when I was showing the specs of my rig, I even clipped the part of it that showed the distro that I was using. One could get a little bit of it with the reference to Gnome, but that was it.
Advertising, at least around here, is also all about Macs (is it really all about Macs in this day and age or is there at least one other OS platform that can do the job?). It seems like a decision that they made x amount of yrs ago is still good today and it may or may not be. Or they don't want to have to upset their workflow that they already have, which I totally get, I really do.
One thing that I have learned as well, through my switch is that some features (not all) is usually a function of a different workflow. It may suck when trying to learn a new workflow, but quite a few of the features that I thought were missing were just implemented in a different way (and it's that way with DRAW v Ai (I rarely use Ps, so everything that I think of Adobe is going to be more about Ai (I used Premier, Audition/Soundbooth and other programs, but in terms of the 2 big ones around here, it's always been Ai to me)).
Don't underestimate too the value of marketing that they have behind their respective brands. Even if they are competitors out there that can what is needed, both companies have that behind them and that is powerful stuff. Especially if it has been proven well in the past. Maybe not so much in recent years, but if it has been true more often then not, powerful stuff.
There was a user on there that always stated that you couldn't be successful in this industry if you didn't have a Mac (quite a few would probably translate that to Adobe as well, couldn't be successful without Adobe). That isn't always the case. He also had quite the ironic siggy, especially when applied to that conversation.
Now, in terms of Ai v. Inkscape. Inkscape will never be able to take over Ai with regard to print (unless don't mind using an extension or a separate program such as Scribus to help) and that can be seen with just Inkscape's choice of file format, SVG. Mainly designed for web work, still a vector, but more for the web. JS interactivity with a file coming from Inkscape compared to any other vector program out there that I've tried is second to none, but until Inkscape comes up with it's own file format, it's going to have some shortcomings with print without some work around. That has always been it's biggest issue (with me anyway, can be work around, but it is a different workflow and takes time to get used to it).
In some other markets an upstart has managed to challenge a strongly established software titan. Look at what SideFX has been doing lately competing with Autodesk. Their Houdini application is drawing users away from Maya and Studio 3D Max. It's going to take credible competition like that in the markets Adobe serves for anyone to mount any kind of credible challenge to Adobe. Right now it's just crickets. Nothing is happening.
Since you mentioned open source, I have to mention Blender in this, especially with the above topic at hand. I would say that Autodesk is worried about Blender given that really bad comparison blog.
A.) They missed a few (more then a few) key features that set Blender apart with it's latest release. Just didn't mention them.
and
B.) The mere fact of them doing something like gives Blender a huge boost in "legitimizing" it as a serious contender (Autodesk obviously thinks something of it to even waste their time with that comparison).
To the OP: Sorry about this. I tried to avoid open source in this discussion as I knew that this would happen.