[Update]: World of Warcraft Classic is giving players a fancy new dragon mount for simply playing Death Knights.
While playing on lower population servers is generally fine due to the Looking For Group system and zones that always try to keep things populated, there is one very annoying problem you'll always have to contend with - a lack of resources. Without a vast array of players to constantly feed crafting materials into the Auction House, making potions and other consumables tends to be a remarkably expensive affair, even at the best of times.
In order to sort this problem out, as well as improve the Auction House experience for everyone, the next update will make it so commodities (gems, herbs, flasks, consumables, etc.) are shared across all Auction Houses in your region. Items that don't belong in that category, like raid-dropped armor and weapons, will continue to be realm-specific.
What this means is that players on lower population servers will likely see a massive decline in the price of consumables, while those on higher population servers probably won't even notice anything has changed. Either way, this is a solid improvement to the Auction House as a whole, and hopefully only the first of many.
Another thing worth mentioning is that Blizzard is looking to create a brand new trade channel exclusively for boosting services. Once this new trade channel goes live, posting about these types of services in the general trade channel will be a punishable offense. Whether Blizzard will actually do anything about people misusing the trade channels, however, that remains to be seen given that Looking For Group is still full to the brim with adds despite them not belonging there.
You can read a little bit more about these changes over at the Blizzard forums. Enjoy, and just in case you haven't heard, the Dragonflight expansion will be launching in 2022!