Have you not got the other chapters for free? Or DH for free?
By that logic they could release chapter 1 for free and never release the rest of the game and still technically create free adult games. There's obviously an implication to the tagline for the company that each game/chapter will be released for free. Again, some delay is understandable. A timely and reasonable manner should be the normal expectation. The free release of Chapter 19 wasn't a priority, not just because patreons got it first, but then in the subsequent months, further paid DH releases were made, and epilogues and then free releases of DH. That's not a reasonable time frame for a chapter to be released. Okay, it's complex, then dedicate the time and resources to figuring that out in a time frame that makes sense for that chapter. The question that's being raised here that's causing mistrust is why other games/chapters were given priority over this free release, which is why people are suspecting that it was intentionally delayed to drive up patreons as much as possible.
We haven't promised a specific timeline for free releases.
You don't have to. There's still a reasonable expectation. If you create a game/chapter in 2019 and don't release it for free until 2029 (I'm being hyperbolic) that's obviously far and beyond reasonable exceptions for a free release even if it's technically still true and viable, and you shouldn't be surprised if it pisses people off. Now, we can have a discussion about what constitutes a reasonable time frame, but simply saying you never promised anything specific is just you playing your get out of jail free card.