I see from an earlier post (can't-edit text-on-image) you are using Gimp 2.8.16 - Is this still true ? Gimp 2.8 text rendering is marginally better than Gimp 2.10 but tiny text will always be "fuzzy" due to anti-aliasing.
The image resolution you start with makes a big difference. If you accept say a default 72 ppi resolution then quality will suffer. If you are sending images out for printing, use 300 ppi. (If all your work is 72 ppi start again)
However, Using Gimp 2.8 and multi-window mode to show a comparison. From the internet I got what I suppose is a typical image. This was 72 ppi and some vertical text from a zippo refill-can, the worst colour scheme possible, white text on black. I make that text size about 8 pix. Using a resolution of 300 text size better at about 18 or 19
screenshot: https://i.imgur.com/TN61ys4.jpg
White text on black suffers in Gimp with fringing, other colours are better but what you can try is Layer -> Text to Path Hide the text layer https://i.imgur.com/9VAf6Wu.jpg
If the text is vertical (Gimp 2.10 does vertical) rotate the path in Gimp 2.8 Then Path to Selection and Paint (not fill) the selection in. https://i.imgur.com/K4serAI.jpg
Turn selection off, hide path
Quote:Is there anything I can do to render the text at a higher resolution and quality?
The image resolution you start with makes a big difference. If you accept say a default 72 ppi resolution then quality will suffer. If you are sending images out for printing, use 300 ppi. (If all your work is 72 ppi start again)
However, Using Gimp 2.8 and multi-window mode to show a comparison. From the internet I got what I suppose is a typical image. This was 72 ppi and some vertical text from a zippo refill-can, the worst colour scheme possible, white text on black. I make that text size about 8 pix. Using a resolution of 300 text size better at about 18 or 19
screenshot: https://i.imgur.com/TN61ys4.jpg
White text on black suffers in Gimp with fringing, other colours are better but what you can try is Layer -> Text to Path Hide the text layer https://i.imgur.com/9VAf6Wu.jpg
If the text is vertical (Gimp 2.10 does vertical) rotate the path in Gimp 2.8 Then Path to Selection and Paint (not fill) the selection in. https://i.imgur.com/K4serAI.jpg
Turn selection off, hide path