These guys:
After two months of arduous combat in a coastal zone of reservoirs and river deltas, Meiktila was taken on 4 March 1945. Two months later, an ambitious amphibious operation allowed Slim’s army to re-enter Rangoon on 6 May 1945. Although this was effectively the end of the campaign, the remaining Japanese forces in Burma did not surrender until 28 August 1945.
And? They were irrelevant to the course of the war - they were cut off from their supply, and were in insufficient numbers to threaten anyone.
The next planned offensive was what is now Malaysia to retake Singapore and re-establish control over the strait of Moluccas. This would have joined up the Southern front to the Western and secured the passage to India.
The problem is that the only way for Japan to actually maintain control over these vast territories is through shipping. They had no overland path from Japan to Korea, to China to Vietnam. Instead, they supplied their troops by sea. Now that they no longer had the forces to supply their troops in Burma and in SE Asia, the forces had to make do on their own. Most hunkered in for attacks that did not come (as they were irrelevant).
Japan had bigger priorities than to maintain troops in Burma when they were under interdict. This the IJN understood back in 1944 with the battle of the Philippine sea. They knew that once their internal defensive corridor was breached that they couldn’t maintain the shipping from Japan south - exactly the problem they faced at the start of the war.
This is why Spruance chose to attack there and not elsewhere. Japan could not afford to lose and would direct the majority of their forces. This was expected.
Japan later on, in the Battle of Leyte attempted to protect their shipping corridor one last time by throwing the remainder of the IJN’s large surface fleet. Checkmate at this point was inevitable but the hope here at Leyte was to delay defeat.