That is due most likely because you are using bad screens and/or bad fonts.
Any computer monitor with a resolution less than 4k renders text with a much worse quality than printed paper. Smaller resolutions may be perfectly adequate for movies and games, but they are not good enough for reading long texts, e.g. books.
Something like a 27 inch or 32 inch 4k monitor is acceptable for reading text. It is still not quite as good as printed paper, but the price of better monitors increases very quickly. At such sizes a 5k monitor would be needed for good text rendering, but those are much more expensive.
You normally sit at a longer distance from a monitor than from a book, so the dot-per-inch resolution of the monitor should be configured so that a page of text should have greater dimensions on the screen than when printed. For instance, for my 27 inch 4k monitor I configure a 216 dots-per-inch value, which results in an on-screen size about 4/3 bigger than on paper, e.g. for an A4 page. I also do not use the default OS fonts, but I replace them with better fonts. Some bad graphic environments may provide no access or only a hidden access to configuring directly the DPI value of the monitor, which is the right way for scaling what is displayed, and they provide only settings that may result in low-quality text rendering, e.g. a multiplier for the size of the fonts or of the windows.
With a good monitor and with well-configured appearance settings in the OS, I prefer very much to read books on the computer display, instead from physical books.
Any computer monitor with a resolution less than 4k renders text with a much worse quality than printed paper. Smaller resolutions may be perfectly adequate for movies and games, but they are not good enough for reading long texts, e.g. books.
Something like a 27 inch or 32 inch 4k monitor is acceptable for reading text. It is still not quite as good as printed paper, but the price of better monitors increases very quickly. At such sizes a 5k monitor would be needed for good text rendering, but those are much more expensive.
You normally sit at a longer distance from a monitor than from a book, so the dot-per-inch resolution of the monitor should be configured so that a page of text should have greater dimensions on the screen than when printed. For instance, for my 27 inch 4k monitor I configure a 216 dots-per-inch value, which results in an on-screen size about 4/3 bigger than on paper, e.g. for an A4 page. I also do not use the default OS fonts, but I replace them with better fonts. Some bad graphic environments may provide no access or only a hidden access to configuring directly the DPI value of the monitor, which is the right way for scaling what is displayed, and they provide only settings that may result in low-quality text rendering, e.g. a multiplier for the size of the fonts or of the windows.
With a good monitor and with well-configured appearance settings in the OS, I prefer very much to read books on the computer display, instead from physical books.