Doesn't really matter what gamexplain opinion is on the matter to be honest. As said, XC2 did release in a same fashion where almost everyone thought it was getting delayed beyond 2017. There's no problem for them to do it with Animal Crossing.
That and I don't see Banjo be in Smash.
I think it all depends on development and scheduling.
There are a lot of first party titles on Nintendo's end that are releasing this second half of the year.
If AC does get delayed to early 2020, its not necessarily a delay in a technicality sense.
Nintendo's fiscal years usually start in March so if AC release before March, its still considered a FY 2019 release.
Not saying AC will get delayed, but there is a technicality to releasing in early 2020.