Yes, of course. Syncthing is not a backup solution. Luckily the amount of data that I have that is considered private and valuable is not that much (~100GB of family photos and videos, some scanned documents) so my backup strategy has been good old SneakerNet. I have a couple of thumb drives that I leave with family, and occasionally get them back to check/refresh.
I keep my data in the cloud, a local (versioned) backup, and for irreplaceable data like photos, i also burn identical M-disc media at least every year. One stored at home, another in a remote location.
While i will probably have worse problems to deal with in case the cloud disappears and my local data is gone as well, chances are that once those are solved, my family photos will not be a problem after those :)
I think for me the original comment was not just about the data, it was also about "what if the cloud disappears".
Financially, it might make sense to pay MS a few bucks an year for a service. Philosophically, the idea is much harder to stomach.
I am far from being a card-carrying member of /r/datahoarder, but I don't like the idea of supporting (much less depending on) streaming services, and I would pay for a subscription service if it was based on open source.
