It's the opposite of short sighted. Biden winning accomplishes nothing. The DNC being forced to listen to the public interest, rather than their rich donors, would be a huge shift.
Anyone that supports Biden is actively pushing us away from M4A and other policies to help our working class, and further cementing our billionaires stranglehold on US politics.
The Democratic party needs to either change, or die off completely. None of this "let's support their shtty establishment candidate and hope they change on their own sometime in the future". That is NEVER going to happen. The DNC will keep propping up corporate establishment goons until voters demand better.