Is it just me or is this a problem?

With recent changes to AP items the best item is now gone. Which item, , its new version a shallow version of its old self. But onto the main point. Mana, mages require it, adc even want it, but with the before mentioned changes, mana during fights is almost to precious to spend, let me explain. Normally kills and assist used to provide you with mana due to old passive which still possesses. But with that gone, fights can leave you oom and harder to push with. To start with, mages clear with abilities, which consumes mana, trying to trade, consumes mana, everything consumes mana. So you end up with less and less as things drag out forcing you to back. Even if you do it perfectly, no mana expenditure that wasn't "worth" (landing all your abilities as effectively as possible), eventually you'll need to back. This is especially bad mid game, late not as much due to large mana pools and strong pushing power, but if you fight for a tower, win, get a tower, then reaching the next tower, enemy's back you might be too oom to stick around much longer. And if you where using abilities to push even more so (unless your adc is up and u just let them clear it, but i mean really? All that CS? No way). So you have to back, likely stopping progress.

P.S. Mana issues in Rift is cruel, but in ARAM, its impossible. I'm building and on champions I would normally never consider it just to deal with the mana issues.