I think it’s not widely front-and-center because it’s kinda fiddly, especially with folks with customized printers and there are caveats that can damage the machine or ruin the print if you are not careful. Sadly, I think that some of the more ‘closed’ slicer/printer systems could support it more reliably because the dimensions of the head + arm are much better known and the tool path can be planned much more precisely.

https://help.prusa3d.com/article/sequential-printing_124589 <-- explains how to set up the sequential printing in Prusa.

https://www.klipper3d.org/Exclude_Object.html <-- Explains the exclude object function in Klipper/Mainsail

https://docs.mainsail.xyz/overview/slicer/prusaslicer#enable-exclude-object <-- how to configure Prusa to label objects so mainsail/klipper can individually select and skip them.

Like I mentioned, I have the most experience with Prusa + my Ender3 ( w/ a RPi3/Kilpper & mainsail; and a crtouch sensor) . I’d wager that other slicers could do this too, but I"m not sure of their setup.

Keep in mind that if you slice multiple parts to be printed at a time, then a failure on one part means the whole batch is potentially compromised.

I have the most experience with PrusaSlicer, and have used the multiple part one at a time option to print multiple parts at once. You have to tell it the dimensions of your extruded head, so it doesn’t crash the part , and if you have a bed slinger, you have to be careful of your x axis bar (ie, order it so it starts at the front if the bed and works it way to the back)

With mainsail and klipper, you can cancel one failed part mid print and keep going on the rest of the parts.

https://pairdrop.net is FOSS, cross platform, realtime, peer-to-peer, and only needs a browser. You can host your own version if you prefer. In contrast, Firefox Send (also FOSS) was ‘asynchronous’ (you could upload, and then email a link), but it was shut down due to abuse. https://github.com/timvisee/send is a fork of the archived github project that you can self host with many improvements, notably authentication, so only yourself and trusted users can upload. (edit: wrong link for ff send)

I worry too – if this gets any significant uptake, what’s stopping Reddit from shutting off the spigot? Given their reasons for turning the screws on API and other policy changes, they may not take kindly to having “their” content re-posted elsewhere, let alone to a system designed specifically to escape reddit.