While it had a lot of competing memes, the Leftist attacks on the Border Wall were totally phony and it was always good policy.
Is it a "solution" to illegal immigration? Of course not. But it could deter illegal immigration in two ways: It would prevent a few people from coming across - maybe more than a few - but its more important function was to act as a SIGNAL to those wanting to come here illegally that they were not welcome.
Biden's wall may physically stop a few people from coming, but his counter-message of the last three years - the Obviously Open Border - so nullifies the Wall's symbolic significance, that it does nothing in that regard.
As for Mexico paying for the wall, it was Trump's plan to place a "tax" on remittances going from workers in the U.S. to Mexican families, in exchange for not tossing their asses out - which Trump was just crazy enough to do.
Maybe in his second term.