Well, not a coward. A non-interventionist stance is in line with a lot of Buddhist ideology which Dragon Ball takes after. A god decided not to get involved with the fate of mortals is a perfectly acceptable norm for many genres deities.
Ever heard of "The Watcher" in Marvel? Same concept more or less. Toriyama is no doubt pulling from such a type.
Is Whis a coward? Of course not. But he has rules he abides by and one of the rules is to oversee, not get involved.
But why do you think he decided not to intervene in the king Piccolo chaos and decided to do so later? Piccolo becoming stronger doesn't matter, because if he weren't to intervene, then whether he was weaker or stronger wouldn't matter.
He spoke about the DBs... Saying he crafted them hoping brave humans could use them for good reasons. And he said he was reconsidering their overall need when seeing how wishes were for selfish reasons, though he noted Goku changed his pessimistic attitude towards keeping the DBs as tools for human development.
When Kami said they could revive him with the DBs, Goku said the DBs would disappear if Kami died... Kami took a long pause and reflected on it. He had talked about the DBs before, too:
Then Kami took Roshi's point and said Goku had the bless to be taught by a great master...
I think it is more philosophical in the sense the DBs represent the way humans can use it, be it for bad or for good... And seeing humans releasing the devil through it may have prompted Kami to see humanity as hopeless. But being inspired by Goku and his friends braveness and pure heart, he offered the God's help for humanity... In a philosophical sense ofc.
But yeah what do you think?
