i maintain the alternative of using open medial vault, if dsm breaks i can boot up omv from a disk or usb and have network access to my files and if synology gets nasty i will just switch to omv (btrfs and SHR are no problem, just work when starting omv)
Just a quick comment on this, if folks do feel the need to start reposturing themselves away from DSM because they are concerned with access to security patches or just have to have the "latest" on whatever platform they want, it would probably make sense to steer away from using SHR - yes it can be supported on OMV or plain old Linux, but it becomes very hard to administrate/fix/assess/maintain once DSM is gone.
For me at least, Docker has freed me from value added services on DSM - those can run on a separate VM or wherever. There are only a couple of things that really, really keep me on DSM:
btrfs. Synology's implementation is the only RAID5 solution that is "safe." btrfs offers dedup/CoW in a memory/compute footprint that is smaller than anything else available, including zfs.
Snapshot management and replication. It's not perfect, but DSM makes these truly enterprise features available on (again) very low cost hardware.
RAIDF1. This is the most elegant and unobtrusive solution to the SSD co-expiry problem that I've seen, and that includes enterprise solutions.
Yes you can get btrfs, or snapshot management on other platforms. But not both together like DSM, and not with RAIDF1. I would love to see something compelling on the other open-source derived platforms that made me want to switch.
having the maintained security updates might matter for some people if the make dsm accessible over internet (like photo station or nextcloud)
i'm more on the side of using vpn to access dsm, makes a much smaller attack surface but will also shut out less IT centered people like family member's
we will see what happens when dsm 7 is out for 1-3 month and i'm not even sure if 7.0 will really have something to offer, i haven't seen anything that triggers reflexes to make it a must have (at least for me)
This is probably an opportunity for this community if 7.0 support doesn't present itself. As long as no Synology update is likely to overwrite them, coming up with a maintainable library of middleware/security updates might be a way to keep XPe going for quite some time. This is essentially what is happening now with the extended driver support via @IG-88's extra.lzma, @The Chief's patches for NVMe cache support and FixSynoboot.
As far as 7.0 goes, btrfs capability (performance, native real-time dedup, etc) is purportedly enhanced. And given the btrfs is getting quasi-abandoned by everyone else in the industry, Synology may essentially be forking their own long-term development of btrfs as a primary contributor (which I guess you could consider both good and bad). So even if we maintain 6.2.3 as a long-term stable niche as above, getting support for 7.0 will likely continue to be of interest to many.