My key point was that there are newer alternatives (the OP asked for that). PyAutoGUI would be another newer alternative. So are Applitools and UIPath, but they are not open-source.

The challenge with Tesseract is that its OCR quality is (too) low for screenshots because screenshots are usually text on colored background. Tesseract is optimized for classical text document OCR. Of course, you can switch OCR engines with Sikuli (I did that before), but this requires touching the source code.