Perhaps someday it will be, but this is called the "nuclear option" for good reason.
Each party has used the filibuster to prevent legislation, or at least force amendments to legislation that they don't like. If Democrats had got rid of the filibuster under Obama, they would not have been able to block Trump's Wall and other projects. If Republicans had got rid of the filibuster in 2017, they could easily find themselves unable to restrain the Biden Presidency in 2021.
Both sides have found it beneficial in the long term to keep the filibuster. This is part of the culture of US politics. Perhaps that culture is changing. Under parliamentary systems, filibusters of government laws are usually impossible. The US system works because much legislation is actually created state by state rather than by the Federal government. The federal government can afford to pass only a few bill with general bipartisan support because lots of the day to day legistative work is done in the 50 capitols up and down the country.