I love your reply, as it puts the finger on what I felt was missing from this simple answer that was otherwise very compelling!
Like there's exploration and exploitation, ikegai is the #2, but something like wanderlust is the #1: the "change/growth/discovery", or what someone else has called "the happy feeling of anticipation of unknowns that comes from a schooltrip/school vacation bus ride": meeting for the first time people who'll become new friends, seeing new things, and not knowing what may happen, yet having no fear of bad outcomes.
It's not exactly wanderlust or serendipity, but something close to that (I wonder if there's a word for it?) mixing adventure/curiosity/freedom and happiness/excitement/inspiration.
Having too much ikegai may prevent it, as it may be become a burden - like you explained about the burden of having to always defend a reputation.
You may need both this and ikegai, like you need exploration and exploitation - a ying and a yang.
> I'm fulfilled by beating the game. Resource acquisition is a Massive Multiplayer game.
Success (in creating then selling a company etc) seems to be just a basic resource acquisition - but then, what?
Getting fulfilled by beating the game may be like metagaming in board games: it may reduce the enjoyment of the game by putting too much focus on the exploitation part.
However, being your own lifestyle company makes it a game within the game: like doing speedruns, or trying to beat a game with each of the playable characters to see the alternative endings
That's the exploration: trying out new options to see if they lead to better outcomes in the future. Like research vs development: there needs to be risk taking before refinement.