Speaking as one of the guilty parties, I'd like to say that in this context, I don't believe we should distinguish between hardware and software modification. They are either both bad, or both good, depending on your approach and your priorities.
Bob Stuart gave a good rebuttal to what Erwin had been doing this year, and talked about all the good things Meridian do to ensure their software performs and functions as well as possible. If you don't develop, test, document and support software properly, all sorts of things can go wrong when someone outside of the factory tackles the job.
However, I think those arguments tend to apply to hardware modifications as well. Electronics have to comply with a lot of regulations before they can go on sale, and the manufacturer is responsible for ensuring its equipment is safe to use. The person that modifies his equipment doesn't have the same obligations, and can't possibly provide the same level of assurance that the modified equipment won't burst into flames while you're out the house. There are lots of other, lesser, evils to avoid as well.
The response is the same - its the owner that is taking the risk
The other issue is licensing. If you build a PC from scratch, you realise that software can be expensive. That's partly because it IS expensive to develop, and partly because consumers CAN be persuaded to pay for it. If you take someone else's software, modify it and re-sell it, then you're infringing their IP. What Erwin has carefully avoided is distributing or selling Meridian's software. He only produces his own SW, which has to use whatever Merdian SW the user must already be using - SW that is already there. Its not the same as pirating MS Office or whatever you may chose to add to an empty PC.
Meridian products aren't sold without software, so there's no underworld supply chain for us to buy cheap Meridian software. In practice we always have it anyway, and Merdian have distributed it for free, so there's no money to be made from what they've done. Anyway, that doesn't seem to be the motivation for Erwin, as he distributed his apodising SW for free, and isn't taking any sales away from Meridian. If Meridian happened to charge for their SW, that would be a different matter, but they don't. Its just a part of the equipment, like the power supply.
Modifying equipment isn't for everybody. Some people won't accept the risks or the potential unreliability, which is fair enough, but that's not a major concern for me. But if you say that modifying software is wrong, then in this context, I think you'd have to say that modifying hardware is wrong as well. And my view on that is that its my hardware, and I'll do what I like with it.
Nick