I have always found those arguments wanting. Consoles are general computing devices. The kinds of applications that drove the EU to mandate changes in the DMA produced by Spotify and Epic are big business on consoles. They are games and a media. Tim Sweeny stated in court that opening up consoles is indeed a long term goal of Epic, he wants Epic to be the universal store on every, and he meant every, device (but don't worry they'd totally be nice and not worry about profit). There is no, as far as I can tell, provision against consoles except that the business isn't big enough in specific areas to fall under the rules. If there is such a restriction that specifically says game consoles aren't affected then I'm even more unhappy with the DMA - some of the US legislation drafts specifically called out mobile devices which is one reason why I think it's even worse than the DMA.
In terms of being sold at a loss, well the Switch was never sold at a loss. Further even if it had been, making low margins or even using the device as a loss leader isn't then an excuse to abuse developers. The whole point is that exercising control over the App Store as Apple does results in unfair business practices within the App Store. That doesn't change if Apple were to sell the iPhone at a loss.
Oh great so towards the end of the product's life cycle the DMA would apply? And it's more than "a bit of profit" towards the end. Your own statement in support of carving out consoles is why this line of reasoning makes no sense on top of all the other reasons above. There's nothing about selling at a loss that says the law doesn't apply to you, you get to do what you want. As far as I can tell, the DMA set the size of marketplace with some very tight numerical terms and some very vague terms like does it provide a "core platform service" and what exactly is a "business user" is defined as, but the reality is Apple fell under the EU's ire largely due to games and media which are the cornerstones of consoles (and yes a few other things).
Because of potential spillover, the more malware and other problems that are generated in the non-Apple EU marketplaces won't stay in there. If it exists, someone will try to submit and will force Apple to spend more resources. Apple already lets stuff slip though, it happens, no one is perfect. But a deluge could overwhelm them.
However, this is why I said later in the unquoted part of the post you referenced that truly malicious compliance would be giving these companies, and apparently the EC, everything they want.