GeoCities. The whole process was designed to facilitate uploading things but at the same time not to hold your hand.
Webrings.
I never had a modem with my Atari ST so couldn't do it, but the magazines of the time, especially the more application / productivity / enthusiast focused ones, always had features on "comms" which was things like dialling into BBSes and stuff. The intellectual barrier to entry meant that you could have informative discussions with people about things without the sort of spackers you get on twatter shitting everything up. Usually this was, yes, pirating software (esp. on the ST where piracy was frighteningly organised; one group in Germany had a mole who worked in a distributor for a lot of games and was in a position where she could borrow a game disk before it was packaged and sealed, bicycle it round to her mate, wait for him to do the crack job - a lot of DRM back then was as now a joke and only deterred casual copiers as opposed to anyone who had assembly language chops so you could literally do it in an afternoon - then bicycle it back the next day). But also it had stuff like programming, hardware modding, and similar.
Speaking of which, the unmoddability of hardware. Related to how everything nowadays is throwaway and unrepairable. Back in the Atari ST days there were a huge variety of mods and tweaks you could make to your system to get it to do things that the manufacturers never intended. The most common was the Marpet board for the STFM. The later STE model had standard 30 pin PC style memory modules so you could have up to 4 megabytes RAM (which was quite a lot back then). But the STFM relied on individually soldered to the board banks of chips. The Marpet board was a circuitboard with a memory controller and 4 megs of RAM pre-installed on it, which you would wire to various pins on the MMU and motherboard to basically bypass the already installed RAM and use that instead. Also popular was the Spectre which plugged into the cartridge socket and contained a dump of the OS and roms from the original Apple Mac and various other things. Armed with the relevant software you could then emulate a Mac, in full, on your ST. This worked because both the original Mac and ST ran on the Motorola 68000 CPU. You could then run original Mac software from floppy or hard drives as you saw fit.
You can't really mod current year hardware like that.
TOS switchers were another one. Basically, the ST had its OS in a series of roms, and there were different versions. But some software complained if asked to run on some versions. So what this was was a board containing the roms for other versions of TOS which was soldered into place atop and parallel to the already installed roms. Also provided was a switch that you drilled a hole in the side of the case and installed there. This allowed you to swap the OS that would be run on powering on.