I cannot use AppSmith without it. For reference, I am following the ticket #518 but there is no mention of this feature in the roadmap.
Unfortunately, for this particular feature request, we don’t yet have a working timeline that we can communicate. However, I’d like to understand your case which might help us prioritize this better. Can you elaborate on your first line, I cannot use Appsmith without it , with a few further details please?
As recommended by Nikhil in the linked issue, please consider whitelisting our IP to access your database directly without an SSH tunnel.
In my personal opinion (read: not necessarily share by the rest of the Appsmith team), whitelisting is a better and safer option than support for SSH tunneling. The reason is in case of whitelisting, you are allowing access to TCP network access on just one port, which is the database’s port to the Appsmith server. However, in the case of SSH tunneling, you will need to share a private key that has SSH level access to the whole server machine running the database server, all in an effort to just access that one port on TCP. Without being paranoid, I think the whitelisting sounds a lot simpler and safer comparatively since the exposed attack surface is lower. Your situation may be very different from what I assume here, so take this with a pinch of salt 
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