CURRENT: ZFS freezes system beyond reboot

Running CURRENT (FreeBSD 14.0-CURRENT #52 main-n251260-156fbc64857: Thu
Dec  2 14:45:55 CET 2021 amd64), out of the sudden the ZFS RAIDZ pool
suffered from an error: 

Solaris: WARNING: Pool 'POOL00' has encountered an uncorrectable I/O
failure and has been suspended.

The system does not repsond anymore on that pool, transactions to and
from that pool are frozen, the system is 99.9% idle.
The most "not so funny" part is: the box doesn't even recognize a
"shutdown -r now" or a brute force "reboot". I still can login via ssh,
but any action regarding the ZFS pool freezes the console/terminal.

ZFS very often renders the system unresponsible forever. How can this
be mitigated? The system in question is on a remote site and it seems
not only to be bound to CURRENT, we realised similar problems on
13-STABLE as well. 

What can I do to "unfreeze" the ZFS? The main OS is, luckily, on an
UFS/FFS filesystem and so not affected from that problem.

By the way, here some more details, as far as I can pick those up:

zpool clear POOL00 cannot clear errors for POOL00: I/O error

Whatever took out the ZFS pool (can not see any hardware errors, the
pool is part of services and especially a poudriere build system and
under heavy load all the time, the box has 16 GB RAM), it also renders
the rest of the system unusable in a way which is beyond a "reboot".

Kind regrads,
oh