Because you presented a dichotomy in which the Democrats are a party intent to "make all your guns illegal", yet that is not their position as a party. Indeed the last Democratic presidential nominee made very clear she owns guns and likes the 2nd amendment.
The opposite is true of Republicans: their party platform is literally "whatever Trump wants", and Trump has actually articulated circumventing the second amendment entirely by "taking guns first".
Moreover, his current administration's stance is that lawfully carrying citizens protected by the 2nd amendment who are obeying the law are at risk for summary execution if his agents feel threatened enough. This makes the 2nd amendment inoperable (no need for a second amendment at all if they can just say they were scared and kill you for having a gun).
If you're going to characterize Democrats as (a lesser) evil, at least be honest about why.