Okay, I wanted to respond to all of these 6 points, so... sorry.
What I really meant is that Bono is running out of new ideas because:
1. He rehashes some key phrases such as "future needs a big kiss" or "begging bowl" or "baby baby baby" or "love and lust".
I noticed that. The middle two aren't as noticeable though. And I wanted to add "vision over visibility" and "because we can, we must." Those are like Bono quoting himself and turning his ideas into lyrics.
2. Songs revolve around the same themes. It was novel when U2 did a Bible-inspired ending with 40. But then other Bible or Christianity-inspired endings came: Wake Up Dead Man, Grace, and something as obvious as the song title itself Yahweh. For NLOTH, the obligatory "God" song was Magnificent.
I never noticed that Magnificent was about God. I thought the first verse was about a romantic partner and the second verse was about U2's fans. But I see where you're coming from, and I actually don't mind it. Somehow I don't think using Christianity-inspired endings is a sign of lyrical stagnation. I think U2 have just always been inspired by their religion and have felt the need to write many songs about it.
3. There is always a war song. Sunday bl**dy Sunday was the origin, but then it was rehashed with Please, then Love And Peace, and now "I don't want to talk about the war between nations".
This, however, is something I noticed and agree with. Don't forget Bullet The Blue Sky. I feel like U2 feels like they *have* to do one because it's expected of them. Either that or the topic of war is still something to get outraged at. But I guess it's not really outrage, and I don't think their more recent "war songs" like Love And Peace Or Else were written with anything specific in mind. So yeah, they're definitely rehashing this idea a bit too much.
4. The rest of the band start getting more lyric-writing credits in the more recent albums, perhaps signalling that Bono's well has dried up?
That's interesting to note and very well could be true. I never noticed that the lyric-writing-credits had changed- I assumed they were credited to Bono and Edge as usual. Will have to go back and look at that...
5. More songs contain the word "love" in it, even up to the b-sides "I can't wait any longer for your love." Why always beat on this theme?
I do agree that there is an overuse of "love" in their most recent songs. But hey, love and romance and anything that falls under that general category is a topic that is easy to write about and lends itself to a lot of interpretations (such as Mercy, which is all about the power of love and what it can do for people, and also uses "love" probably more times than any other U2 song). Love is something that can always be relied on for inspiration, I think. I don't find anything wrong with using it over and over.
6. Some songs are just filled with cliches and common metaphors or figures of speech, they sound forced and unnatural.
Yeah... "ATM Machine..." "Intellectual tortoise (what the heck even is that?)..." But I don't notice that as much. It would be helpful to point out some examples that I can't remember off the top of my head.
I don't think lyrically "bankrupt" is exactly the right word. Maybe something that implies decline of creativity would fit better.