It certainly fits Sun Tzu strategy, when the whole world is focused on SCS and the X-Island Chain concepts, China suddenly gains a coastline in Myanmar lol
However it's impossible. The strategic gain for China would be so enormous that I just can't see how India and the US don't actively intervene to stop that from happening. It would be a disaster for them to allow such a thing to happen
How would they be able to intervene when the country would not even hold a few hours if China wanted a takeover? US, let alone India, could not stop a Chinese annexation of Myanmar anymore than China or Russia could stop American annexation of Panama.
It's social factors that make China take it slow, Myanmar is extremely poor and underdeveloped. Militarily, China could take it in a day, but the occupation would maybe significantly tax even the giant Chinese economy. The area is all villages and mountains.
If you let an ethnic Chinese minority slowly inch towards total takeover, they'll develop all the institutions, and then let them propose joining China on their own. Then China can just say yes without alienating anyone.
There is also the matter that there will always be cultures that disagree with joining another country. If China were to own Myanmar from tomorrow onwards, these peoples need to be dealt with somehow, the resulting crackdown may tarnish Chinese international reputation. Whereas whatever MNDAA does is their own business only.