Based on your experience, using fstrim is at your own risk! I add in the fstab mount command options of noatime and discard for the ext4 partition type. I can add in noatime for all partitions types and gain speed. Here are the fstab settings I use:
Don’t let yourself get upset by all the alarming stuff out there. If you’d have to go through manual trimming, IMHO (and others’) something would be seriously wrong with linux. Again IMHO, distros should use noatime and discard as default for partitions on SSD’s, since it’s advized to do so by the kernel people.
To get back to my first line: my 6 year old 30GB SSD is still working despite of no tuning whatsoever and stressing it all the time. In fact, I have had serious issues with HDD’s but the first SSD problem has yet to appear
I have used fstrim on my Intel 330. My understanding is that it always returns the number of bytes on the partition you have run fstrim on, hence the large number. Of course the number of bytes cleaned up would be more useful, but so be it… Using fstrim periodically has not caused me any problems. Though with my SSD I have enough free space and no IO issues at all so barely remember to run fstrim.
From what you say it sounds to me like a faulty package update problem rather than the SSD. I have found from past experience that accepting all package updates can lead to boot failures. So two suggestions 1) either use fstrim but hold off making any package updates, does everything then go well? 2) clone SSD to a spare mechanical hard drive, apply all the package updates, does that also lead to the problem?