These numbers are actually promising. 400 sales in early access for a 'niche' game would open the door for a few publishers out there. And as it stands this game has momentum behind it, NOT an easy thing to accomplish.

And further more, the steam page has quite a few problems that are easily fixed and would drives sales in a positive direction. Add some streamer outreach to the mix and this could do well enough to fund their next game. Just perhaps not well enough to satisfy the developers ambitions. Yet.

I would love to have this momentum on my own (very) niche game. Its is also on early access, interesting premise, zero marketing budget, and so on. Its numbers are nowhere near as promising as Yerba Mate Tycoon. Its a rare thing to click with an audience and YMT has done so.

To the Developer, keep going. Keep that mindset of honouring your customers its rare in games and of value to the gamers. Spend more time on you store page and promoting, and release it. It will be worth it.