I take a baby aspirin daily.
But it seems like the most recent clinical studies have cast some doubt on the practice as a general rule.
Our bodies are in a fairly precise balance without drugs. What I mean is, blood that's too "thick" and clots too easily carries a lot of the dangers that aspirin alleviates. But blood that is too "thin" and does not coagulate normally also has downsides - small bleeds that otherwise would have healed may not in the presence of blood thinners, including aspirin. Plus there can be gastrointestinal issues with aspirin.
Hence the current state where only those with certain risk factors are having daily aspirin recommended to them.
And back to the OP, sitting still for extended periods may, in fact, be one of those risk factors.
For now, I am continuing to take mine.