Unsubscribe from ALL mods, missions and compositions from Steam Workshop
Restart ARMA 3 and Launcher so there are ZERO mods subscribed.
Subscribed to 3200 mods.

Let it download and populate the launcher.

Note the FIRST few mods for reference such as CBA, CUP or RHS.

Subscribe to handful of additional mods.

Check the launcher and note it will DOWNLOAD it, but not show up in the Launcher itself.
The !Workshop folder symbolic links are NOT created after hitting this limit.

Next, close STeam and A3L.
Start Steam and let it update
Start A3L
Note A3L wil begin to REMOVE the first few mods from the launcher and symbolic links from !workshop folder, but not remove the contents.
A3L will being to create mods 32001-on's symbolic links but only up to ~ 3200 symbolic links.

You can repeat this keep subscribing to NEW mods. A3L will remove the symbolic links for the next oldest mods, while leaving the local content alone, remove it from display in A3L, then ADD the new symbolic links and let it show up in A3L.

Example:

Mods 1- 3200
Subscribed to mod 3201
Mod 1 is removed from !workshop but local contents still exists and will be updated
Mod 3201 symbolic link is created and shown in A3L

Subscribe to mod 3202
Mod 2 is removed from !workshop but local contents still exists and will be updated
Mod 3202 symbolic link is created and shown in A3L

Subscribe to mod 3203-3210
Mod 3 is removed from !workshop but local contents still exists and will be updated
Mod 3203 symbolic link is created and shown in A3L
Mod 3204-3210 not shown OR

Mod 4-10 is removed from !workshop but local contents still exists and will be updated
Mod 3204-3210 symbolic link is created and shown in A3L

It updates depending on Steam Workshop scheduling.