I have Sequoia MacOS. The above suggestions do not work for TurboTax on my Mac; there's no "format" icon or button. However, after talking to Apple TS, we were able to change the text size on TurboTax by changing the display resolution. Open the TurboTax (Mac) app, go to System Settings, then Displays, then turn on "show all resolutions". Select a resolution lower than what you have been using. My default setting was 3072x1728. I selected 2560x1440 (high res, not low resolution). This was my comfort text size. You choose what works for you. I hope this works for you.
