I noticed this too, since the macOS 12.2 update my Intel-based 2019 iMac wakes up from sleep every minute, then seemingly goes back to sleep, then wakes up again, in 1-minute cycles.
Looks like it's some peripheral, potentially Bluetooth related. The only BT devices connected are the Apple keyboard and mouse that came with the iMac. I tried an SMC reset but didn't help.
$ pmset -g |grep "sleep prevented"
sleep 60 (sleep prevented by bluetoothd)
I see a bunch of these sections in pmset -g log
2022-02-06 21:58:10 +1100 DarkWake DarkWake from Normal Sleep [CDN] : due to EC.DarkPME/Maintenance Using AC (Charge:0%) 43 secs
2022-02-06 21:59:10 +1100 DarkWake DarkWake from Normal Sleep [CDN] : due to EC.DarkPME/Maintenance Using AC (Charge:0%) 46 secs
2022-02-06 22:00:35 +1100 DarkWake DarkWake from Normal Sleep [CDN] : due to EC.DarkPME/Maintenance Using AC (Charge:0%) 47 secs
2022-02-06 22:01:52 +1100 DarkWake DarkWake from Normal Sleep [CDN] : due to EC.DarkPME/Maintenance Using AC (Charge:0%) 45 secs
2022-02-06 22:02:45 +1100 DarkWake DarkWake from Normal Sleep [CDN] : due to EC.DarkPME/Maintenance Using AC (Charge:0%) 45 secs
2022-02-06 22:03:38 +1100 DarkWake DarkWake from Normal Sleep [CDN] : due to EC.DarkPME/Maintenance Using AC (Charge:0%) 46 secs
2022-02-06 22:04:35 +1100 DarkWake DarkWake from Normal Sleep [CDN] : due to EC.DarkPME/Maintenance Using AC (Charge:0%) 45 secs
2022-02-06 22:05:27 +1100 DarkWake DarkWake from Normal Sleep [CDN] : due to EC.DarkPME/Maintenance Using AC (Charge:0%) 46 secs
2022-02-06 22:06:25 +1100 DarkWake DarkWake from Normal Sleep [CDN] : due to EC.DarkPME/Maintenance Using AC (Charge:0%) 45 secs
2022-02-06 22:07:17 +1100 DarkWake DarkWake from Normal Sleep [CDN] : due to EC.DarkPME/Maintenance Using AC (Charge:0%) 46 secs
2022-02-06 22:08:10 +1100 DarkWake DarkWake from Normal Sleep [CDN] : due to EC.DarkPME/Maintenance Using AC (Charge:0%) 45 secs
2022-02-06 22:09:04 +1100 DarkWake DarkWake from Normal Sleep [CDN] : due to EC.DarkPME/Maintenance Using AC (Charge:0%) 46 secs
2022-02-06 22:09:57 +1100 DarkWake DarkWake from Normal Sleep [CDN] : due to EC.DarkPME/Maintenance Using AC (Charge:0%) 46 secs
2022-02-06 22:10:56 +1100 DarkWake DarkWake from Normal Sleep [CDN] : due to EC.DarkPME/Maintenance Using AC (Charge:0%) 46 secs