Opinions on abortion and taxes are entirely moral judgements, so if the university system is swaying its graduates' opinions regarding them, this confirms what its critics say: that the system is a form of indoctrination.
Not to mention the medical issues that pop up where it should be explicitly legal, like with young teenage girls or rape victims.
Illegality never stops everything, it’s just some subset of embodied ideals.
For drugs there actually is a strong argument for applying the same logic to legalise and regulate them, as it may well reduce harm.
Also, on the issues you mention (abortion and taxes) the GOP is more moderate than before. Trump is the first GOP candidate ever to oppose total abortion bans. He also was the first to take entitlement reform off the table.