If you're replying to me, you're the one that clearly doesn't know what they're talking about. I'd love to hear how they would fit over 100GB of data on a 100GB PS5 disc or on a 50GB Xbox disc. If you're replying to the OP, I agree with you.
Discs are cheap, it costs them nothing to put 2 discs in the box, or even 3. Games have done this, many times.
FF8 on PS1 had 4 discs. Baldur's Gate 2 on PC had 5 discs. And you could say, "well but that's CDs, they couldn't fit that much data so of course". That doesn't affect the cost of pressing a disc that much, and let me tell you, several gigabytes of data was a LOT for the time.
Blue Dragon on the Xbox 360 also came on 3 DVDs, Lost Odyssey on the same console came on 4.
Bluray games have largely come on a single disc, not because they are expensive to make, but because a single bluray used to be plenty of space.
That isn't the case anymore, so why should we not expect games to come on multiple blurays when they can't fit on a single one, as they have in the past with both DVD and CD based games?
The problem is not that the game won't fit. The problem is that the companies are too cheap to even press discs nowadays. Even if the game fit on a regular DVD, they would still just give you a code.
The install speed from bluray might be slower than the internet speed of many people, but that's besides the point. Online licenses can be revoked, and cannot be easily transferred (or often at all). Physical copies of games cannot, and you get to do as you like with them. I'm not surprised that companies prefer to give you license they control rather than pay to manufacture physical copies that they cannot. More just disappointed.