There's a lot of things it affects. But lets stick with the self serving perspective of your question "How does this affect* me buying discounted games". You personally? Not much, the impact is relatively tame... for now. An aspect that you failing to consider is that devs could raise price of games to offset the cost of the Unity price model change. Sure you could wait for a discount. Safe to say we all appreciate a good discount every now and again. But I encourage you think about that "one" game on your wishlist "If it was just 20% less then I would buy it" But that 20% doesn't end up happening because of the fact that even during this hypothetical sale the devs are still trying to offset the Unity cost. Additionally you failing to consider is that Unity is an incredibly popular starting point for many new devs because of the tooling it has available, many popular titles were started by these indie devs. Games that wouldn't ever have been created because those people wouldn't have ever gotten started if they didn't use Unity.

You're acting like this reflects badly on the console makers when a) they haven't confirmed they are on board for this and might instead end up being the ones to kill it, and b) if they were on board for this, they still wouldn't be the bad guys, they'd be helping out devs on their platforms.