Building a brand is a fine answer, but this is incorrect:

> The most obvious answer: TechPays caters for countries not present on eg levels.fyi - see how there are no data points for eg Estonia, Hungary, Belgium etc.

All three of those countries have submissions on levels.fyi.[1][2][3]

[1] Estonia: https://www.levels.fyi/comp.html?track=Software%20Engineer&c...

[2]: Hungary: https://www.levels.fyi/comp.html?track=Software%20Engineer&c...

[3]: Belgium: https://www.levels.fyi/comp.html?track=Software%20Engineer&c...