What does it mean that Myanmar can be seen as part of South Asia in some art circles and Southeast Asia in others? Does it have to be one or the other and why does it matter?

As borders are constantly redefined and history often rewritten, art historians, curators, and galleries make judgment calls on what is emphasised. Of course money and power do the talking, but mostly money.

http://frontiermyanmar.net/en/art-history-myanmar-south-asia