I’ve reported this issue in the first place. I agree that manually adjusting the spacing would be very tricky and the too little or too much is subjective. I’ve tried to make screenshots of different sizes. I'm not an expert but I think the -webkit-text-size-adjust that you've mentioned doesn't necessarily define a suitable line-spacing in every situation. There are many articles and tools to calculate the ratio between text size ~ text width and line space e.g. https://pearsonified.com/typography/

I requested this too, and I think it's in particular important now that more iPads are paired with keyboards. The problem arises when a user, who is using a keyboard, switches from an another app (e.g. Safari) to Wikipedia. Then, he is suddenly in an app that just doesn't work with a keyboard and completely breaks the experience and purpose of the app.