I noticed this game requires ~700 MB of space despite being a text adventure.

I almost downloaded it but then decided it would be wiser to avoid it, owing to the fact that such a huge install for a text game has a high chance of potentially having something sketchy in it, such as malware.

Another possibility is that your game contains huge amounts of uncompressed audio files. If so, have you considered using MP3 (for lossy audio compression) or at least FLAC (for lossless audio compression)?

It could also be the case that you've built the game on a very bloated engine or library or language runtime.

In any case though, my point is that the size of this text game is so huge that it gives users a lot of reason to hesitate downloading it. You could expand you audience a lot (potentially) by fixing that.