I think if you don't have the luxury of being able to delay work untill you have solid wi-fi, it makes a lot of sense to travel to areas where you know there is consistent wi-fi. So unfortunately this might mean avoiding poor wi-fi areas. On the plus side, there is so many amazing places to travel that do have great wi-fi!
Secondly, consider getting a local sim card with some data. In many countries the data cards can be quite cheap and are an essential backup if you absolutely need to get work done at certain times because as you mentioned, sometimes good wi-fi is nowhere to be found.
Thirdly! Plan ahead, even if you're in an area with poor internet generally, make a post on our forum, or join a local digital nomad group on Facebook and ask the experienced nomads where the good internet is at.
Hope this helps!
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