I didn't watch the debate but this sounds like a good summary from what I have now watched and read.
The VP debate offers the nation a glimpse of a post-Trump future.
The restrained sparring between Pence and Harris was a reminder of what politics was once like — and could be again.
www.politico.com/news/2020/10/08/vp-debate-post-trump-harris-pence-427765
Let's say this at the outset: This was a boring, unfocused debate between two well-prepared and polished candidates who had little interest in answering the questions posed to them — and were under virtually no pressure from the moderator to do so.
...
Harris and Pence are both younger, more well-spoken, and closer to the beating hearts of their respective parties. Considering the challenges anyone would have defending the Trump record on the pandemic, Pence’s ability to leave the stage after 90 minutes without being gutted by Harris was a bar cleared.
...
Harris was well-prepared but restrained. She did not, as previous vice-presidential candidates have — including Joe Biden in 2008 and 2012 — play the role of vicious aggressor. In previous presidential campaigns that role has sometimes diminished the running mate.
Whether by design or happenstance, Harris seemed more interested in coming across as civil and presidential rather than as an attack dog. Considering the dynamics of the campaign that may have been a politically astute decision. She and Biden are well ahead in the polls and defining Harris as someone ready to be president, rather than as a political assassin, may be a more important use of her limited time in the spotlight.