Easy fix really. The PS5D can be marketed as a "subsidized" console. Kinda like how you have amazon fire devices. The machine can even be "ad-supported" if sony decided to take it there. Where when you log on you have a slightly more "ad active" home page than what you would otherwise have on the standard SKU. But that's even going too far. All they have to do is market it as a subsidized console being that the only way to buy content for it would be through the PlayStation store.
Everyone would get that.
Like I said above, the marketing, if there's such a large discrepancy (anything above $50), would be to make it sound like the reason one is cheaper isn't because of a lack of a Blu-ray drive. The smart thing to do would be to instead make it clear that that version of the console is more subsidized because the PS store is the only way to get content on it. No used games...etc.
Some would get it. I would understand, though I wouldn't exactly be happy per say. Digital is not an option for me even if I wanted the cheaper model. It has to be the disc based version. Since I understand the difference should technically be $50 at most, any more gap than that would be justifiably worthy of complaint. Now since I'm not one to complain in general, plus I understand the marketing and business decisions behind why they may do that, I wouldn't complain, but there's plenty of people out there who don't fully understand, or would just complain regardless.
We subsidized one but not the other, only helps those who want the digital version. Using the PS store as an excuse really ain't great because you're making it more obvious used games can't be shared. This was a major problem before the XB1 launch. You could also easily say SNY doesn't care about the hardcore gamer or gamer with poor internet. Remember what happened the last time a console company decided to screw over gamers with poor internet? PS5 digital is for those who have good internet and if you can't get that, we have another cheaper product for you, it's called the PS4...
Just pointing out a possible downside to making the gap too large. Maybe a blind eye would be turned to it, who knows? Just something they would need to take into account if they were going for a $100 gap or larger. Even worse perhaps if they try to bundle free games with the digital version to make it more of a value compared to XBSS. We'll see what they do though. Maybe they'll surprise everyone with $349 and $399, and then nobody will complain about anything.