This is a huge problem.
The new hosting system cannot replace the utility hostbots provide.
Most importantly:
-Autohosting. Many players on Warcraft are here for one or two custom games such as Legion TD which they play exclusively. These popular maps have autohosts, which have several benefits, which include:
-Hopping on and playing is extremely easy. You know which bot to join, the game is always online.
-Quality control. You know what version of the map you are playing, you know the community you are joining, and you are not going to get kicked by a random host.
-Competition and elo. Autohosts for popular maps can be played competitively thanks to the elo system hostbots can provide. Example:
ENT Gaming This site provides not just elo tracking, but also the ability to see your game history and view the chat and replay.
-Entire communities are built around hostbot systems. I am a moderator over at ENT. We have a set of rules (mostly simple things such as don't refuse to play) and the bots are moderated (only on autohosted competitive games). The players that play on our bots enjoy this as it allows for a competitive environment. I have over 3000 posts on the forum and have spent years moderating this community, and in one patch this will all be thrown away.
Other things:
-Low latency: This affects a number of competitive games such as Warlock which requires lower latency and are now essentially unplayable.
-Flexible hosting location: On ENT you can host from many server locations that you would otherwise be unable to.
-Online hosting list: the popular services entgaming.net and makemehost which hosts 90% of the games on battle.net have their own lists, making it incredibly easy and convenient to find what game you want to join. This is far better than the ingame list which only contains a fraction of the games hosted.
-Complete host control: in addition to autohosting there is a public hosting system. This allows users to utilise kick functions, maintain a ban list, set latency, set synclimit, and countless other benefits.
Throwing away bots already is destroying these communities, and there is not a good enough system to replace it.