Procedurally, 'top ten photographers' seems harder to execute than 'top ten photos with only one photo per photographer' (comparing someone's entire set of submissions is just.. hard). But that is more a matter of execution than a value statement.
As for restricting who can participate: This is definitely up to the national team, and I know some countries have done so in the past. I would be cautious with the word 'native' of course, but that's mostly a matter of phrasing and political sensitivity. I suspect you mean 'inhabitants'.
If you restrict yourself to inhabitants, you should consider how many high quality images that would leave you with. If tourists are your main source of high quality images, would banning them from the competition help or hurt your goals? What are your goals exactly anyway? Are there other ways to achieve them? (think about special awards etc)
But also consider: how will you enforce it? How will you verify that someone is an 'inhabitant' and what is your definition? For example, someone who spends 3 months per year in Suriname, would they be allowed to participate? And 6 months? 9 months? How would someone have to prove that they meet that definition?
In general, I always caution for rules that are negative in their nature: they have a tendency to mostly push people away, rather than encourage new participation from the group you feel you want more participation from. At least in the short term. It might be worth thinking about what positive measures you can think about towards that goal, how you could encourage and facilitate participation from people who currently live in Suriname.
Just my two cents :) This is definitely not a new conversation, and it's great to see people chime in with their experiences!
Lodewijk