Whats the Point to These Items?

Mana regen was basically scrapped for non-support mages in favor of building flat mana. Okayyeahsurewhatever. Got it.

So then why did Rod of Ages, one of only TWO major mana items for AP champs, get it's maximum mana chunked down to 400 from 850? Not only is that a huge nerf in general but, combined with the 20 points lost on AP, costs 33.5 mana when combined with Archangels. That's not an uncommon synergy and certain champs (like Karthus) rely on it. Factor in the Rabadons and its now a 45-point AP loss. Kiss another 40 points of AP goodbye if you did what you're practically forced to do and bought a Zhonyas. Why is this supposed to be a good idea?

Allow me to point out that when Marksman lost flat damage on THEIR items, they were compensated by monstrous amounts of crit, burst damage (for the class that shouldn't have it) and tons of movement speed in any of four VERY cheap items. They also got PHYSICAL SPELL VAMP and two % damage negation items. To top it off, they got Essence Reaver with its top-tier damage, 20% crit, 30% CDR and infinite mana for the class that ALREADY has the highest base mana regen at 18 (if you didn't know that, surprise! Jinx has the most!).

What did mage items get? Complete loss of mana regen in combination with an increased need for it, major net losses to AP itemization, nerfed maximum mana and a couple new hextech items that are far worse on them than the AP assassins who are going to abuse them with it. Oh YEAH. That brings me to my next point:

Good luck surviving against Ekko, LeBlanc or Diana when they have their pick between an AoE slow or ANOTHER dash combined with even MORE free burst damage. It's bad enough that they could already stat-check you straight up, but now they can have an even greater threat range. Why was that a good idea?