Previously, the flaw was that draw-calls never expired, meaning an early offer could still be accepted much later to avoid a loss / not letting the enemy team win when the match situation has drastically changed.

The fix is not live, yet, but is in the pipeline.

As @maudlin27 already explained, no one should be banned for drawing a match. If you encounter situations where a draw was abused to tamper with the game state, please report them for investigation.

Rating manipulation is against FAF rules, so if the game was rated, and it was reported, and the mod reviewing the report thought it indicated manipulation (i.e. deliberately drawing a game that was won to lower your rating) then you could be at risk of a ban, but even in that scenario you could then appeal the ban and explain what happened.

Unless there's a pattern of it happening in other games then I'd have thought it relatively unlikely you'd be banned, and even more unlikely you'd remain banned on appeal, subject to if there's evidence contradicting this.

Translation for Nuggets:
No, it shouldnt result in a ban

The problem here is the reply by maudlin going into rating manipulation without actually responding to the OP. When just looking at these 2 posts it looks to me that a moderator replied that this is bannable and he might have to "justify" himself in a ticket.
Not to mention the OP went out of his way to ask and talk about it instead of just doing it (and then repeating).

Nobody will care about some random beef about drawing or not drawing a single matchmaker game. Have some faith in the mod team

Not to open a big topic here, but this thinking is the reason there are stupid edge cases or rare cases that are bannable. Nobody care != Not bannable (which is the problem)

Unless there's a pattern of it happening in other games then I'd have thought it relatively unlikely you'd be banned, and even more unlikely you'd remain banned on appeal, subject to if there's evidence contradicting this.