The realm is basically being DDoS'd by the amount of players that are playing. In order to maintain a playable state of the game, the realm disconnects players that remain AFK in certain locations for long times and it also disconnects people that are doing nothing or barely anything in popular locations.
For example, if you are spending too much time in Dalaran simply idling, or just going around doing minor quests in Dalaran for more than an hour or two, it'll disconnect you to make room for players that actually want to play. It does not discriminate between contributors and other players. These measures are mostly targeted at players who are idling in Dalaran, so most locations do not have the same measures lined up.
We are making countlesss measures to combat this and to continue making the realm a playable place. You have probably noticed it, but the average server latency has increased, this is a direct result of increased numbers of players. One of the measures, we are already doing is making two Dalarans that work with each other seamlessly so players will not notice it, but in fact we will be running two Dalarans, one instanced and one in the real world. Other measures are temporarily lowering visibility distance but even so the average player has hundreds of players in their immediate view distance.
To make the realm more playable, you can do a simple thing yourselves, avoid popular places and spread around more, enjoy what the game has to offer instead of idling in one place. This will directly impact the playability of the realm. After all, these are unusual times, both in real life and in-game, but we will adapt, as we have always adapted. We are monitoring the situation on all realms around the clock 24/7 and more measures to ensure stability can be expected.