well, the claim is more, that there aren't that many catchy choruses, and the ones that are there aren't any good, but that's of course subjective.
However, you may seem to notice, the main qualm people have with the album isn't that of lacking catchiness, but that of monotony.
To elaborate on that, here my very in-depth, very scientific analysis, track by track:
1: NIHIL 80bpm, B-flat minor, intro, electronic
2: Headache Man var. 1 100bpm, B-flat minor, Heavy GurrGurr song
3. Headache Man var. 2 120bpm, B-minor, Heavy GurrGurr song
4. Headache Man var. 3 150bpm, B-flat minor, Heavy GurrGurr song
5. DERACINE 75bpm, B-minor, Power Ballad or sth
6. Headache Man var. 4 110bpm, A-minor, Heavy GurrGurr song
7. Ruthless Deed v2.0 90bpm, A-minor, Heavy GurrGurr song
8. Headache Man var. 5 105bpm, B-minor, Heavy GurrGurr song
9. Hyena v2.0 100bpm, C#-minor, Heavy GurrGurr song
10. Headache Man var.6 120bpm, A-minor, Heavy GurrGurr song (with little ballady bits)
11. Headache Man var.7 120bpm, B-minor, Heavy GurrGurr song
12. Headache Man var.8 120bpm, D#-minor, Heavy GurrGurr song (with little ballady bits)
13. Headache Man var.9 145bpm, B-minor, Heavy GurrGurr song
14. OMINOUS 90bpm, D#-minor, Song
now, if i wasn't such an asshat i might give them, that Hyena 2.0 (i think it's real title is lucy?) is more of a punkrock track than gurrgurr, that maybe the gurrgurr/balladybit songs have a more suitable example than headacheman, but you get the picture. the overall impression of the album is, that more than 2/3 of the songs are more or less slight variations of sth like headache man, somewhere between 100 and 120bpm, probably in B or B-flat minor. On DIM you had one headacheman (maybe adding moth, leech and ogre to the same realm, but that's about it), which is why people loved it so much. Here you have a full album consisting of one single track, that in the end just feels like an hourlong forgettable slob of generic riffwankery.
(which isn't helped much by the fact, that they once again fail to chime in on the possibilities of having two guitars. I mean, double-tracking is cool and all, but when the rhythm and the lead guitars are just carbon copies of each other for 90% of the time you really are doing sth wrong, or are being very lazy)
Edit: Also, having listened to the album a few times more now, i change my rating from 6-7/10 to more of a 5.5/10 due to severe boredom