Great article. What if not Synology?

[Enquiries]

I've only had one NAS in the past 14 years. Synology DS212j. Both 2TB disks have been replaced once in that time.
I stopped updating the OS many years ago when one of the updates temporarily bricked it.
I used to experiment with hosting web site, music server etc, but it seemed to slow to a crawl for file access after that and even when I removed these services, never sped up.
Then last year the connection to the NAS by MacOS suddenly disconnected every time the MacBook would go to standby which has been annoying,but presumably that is a MacOS update that is responsible.
So I want a new, fast NAS, probably mainly for file access and phone photo backup. One that "just works" and works seamlessly with MacOS, Windows, occasionally Linux, iOS and Android.
It would be nice if it offered other services like media server, computer backup, web/FTP server etc, but as long as it does a reliable job serving files, that's the main thing. What do you suggest?

[ed]

If you want something that behaves as trouble free as possible with macOS, Windows, Linux, iOS and Android, Synology is still the safest recommendation for the use case you described. DSM remains the most polished operating system for simple file serving and photo backup, and its SMB implementation is the most consistent with macOS. A modern model will feel dramatically faster and far more stable than your DS212j. A DS224 plus or DS423 plus fits comfortably in your budget and will be several generations ahead of what you are used to.

If you want to avoid Synology entirely, the closest alternative in terms of ease of use is QNAP. Their QTS software is more feature rich than DSM and works very well for file serving, Time Machine, Windows sharing, and mobile photo backups. It is slightly more technical than Synology, but still friendly enough for home users. A QNAP TS 464 would fit your needs and budget and will give you much more performance than your old system.

UGREEN is another option worth considering. Their recent NAS models have impressed many users with very fast hardware and a simple interface. They are newer to the NAS market and the software is evolving rapidly, but for basic file access and phone backup they work well.

Given your requirements, the simplest guidance is this.
If you want the most polished and stable experience, choose Synology.
If you want more hardware power and still a simple interface, choose QNAP.
If you want very fast hardware for the money and do not mind a newer platform, choose UGREEN.