Installed linux-{image,modules}-6.5.0-1008-raspi from mantic-proposed and verified that the DTB is gone:
$ file /lib/firmware/6.5.0-1008-raspi/device-tree/bcm7445-bcm97445svmb.dtb
/lib/firmware/6.5.0-1008-raspi/device-tree/bcm7445-bcm97445svmb.dtb: cannot open `/lib/firmware/6.5.0-1008-raspi/device-tree/bcm7445-bcm97445svmb.dtb' (No such file or directory)
Installed linux-{ image,modules} -6.5.0- 1008-raspi from mantic-proposed and verified that the DTB is gone:
$ file /lib/firmware/ 6.5.0-1008- raspi/device- tree/bcm7445- bcm97445svmb. dtb 6.5.0-1008- raspi/device- tree/bcm7445- bcm97445svmb. dtb: cannot open `/lib/firmware/ 6.5.0-1008- raspi/device- tree/bcm7445- bcm97445svmb. dtb' (No such file or directory)
/lib/firmware/
Previous kernel: 6.5.0-1005- raspi/device- tree/bcm7445- bcm97445svmb. dtb 6.5.0-1005- raspi/device- tree/bcm7445- bcm97445svmb. dtb: Device Tree Blob version 17, size=6147, boot CPU=0, string block size=475, DT structure block size=5616
$ file /lib/firmware/
/lib/firmware/
Also verified, that a Pi 4 B still boots with this armhf kernel.