The two Supreme Court justices who did not join in to dismiss the Texas case made it clear they approved of the procedural right to bring the suit, but disapproved of the substance of the case. For those who take comfort in that, you would have lost in any case if a SCOTUS vote had ever happened.
The idiocy of the substance if it were upheld means the precedence would have been set for Texas to sue Colorado for having years of universal mail-in voting. Their case: would have to be on the basis that Texas was harmed someway. Perhaps it was because they opposed the electoral college vote results and all Colorado's mail-in ballots de facto were fraudulent?