I don't feel the trilogy era was super positive but I have fond memories of quite a lot of the promo, like the Radio One interview where Billie played clips of songs and got in trouble for it It was fun waiting for the next video that led up to the release and I remember the excitement when I saw this one especially:
It was exciting waiting for the next secret show too, wondering what new songs we'd hear and gradually finding out what each one sounded like. We know now that they were pushing themselves way too hard and the albums didn't turn out as they hoped, but it came across (to me, at least) that they were full of excitement and had high hopes at first.
Some of it was questionable for sure and I did think that even at the time. I still feel uncomfortable when I see the photos/videos around Irving Plaza and that general time before iHeart, especially some of the stuff Billie was posting on Instagram. There are quite a few quotes from then that sound nothing like him and are weird to see, too.
But I don't know, I don't see it that negatively otherwise. Makes a difference that I liked the music, of course. Though when I think about it, as incredible as the 21CB era was they were obviously exhausted by it - Billie has said a few times that the album drove him crazy. I don't view that as so different to the effect the trilogy eventually had.
As for the album covers, they are very ugly but I kind of like them in a weird way now I dyed my hair pink and green back then and it matched my Uno Converse. A lot of the album art came across as quite lazy but a few of the pages were great, like this one