A party where everyone's down if they get 3 arrows from the goblins and each goblin is lucky to still be up after 1 hit and mostly we just roll a hit roll and a damage roll is a short fight. Later fights have instakill spells hitting and that also shortens them**
Having some players using the simpler classes would help (especially those who think more slowly or are less organised when their turn rolls around*). But those same classes tend not to hit as hard from what I read on optimisation sites, so each round is quicker but you have more rounds.
* yes, I am very carefully not being disrespectful to those with who can't do these things. I've been through roleplaying while caring for small kids, in illness and with people who are not neurotypical. We all have stuff going on some times
** No, instakill spells being out of balance with fighters is not a good thing. But "Save or die" is fast