ok sorry, i was trying to put my daughter to bed when i wrote the reply above
so i think the examples of Thuram and Kane - they're both late bloomers is many ways. It took them a while still to really, consistently, break into their first teams and be bigger names.
Pio, on account of his Serie B season, COULD (potentially) have a pretty solid season in Serie A next year, but only if he gets the chances to do it. He's demonstrated he's probably one of the better players in Serie B, so we could 'waste' him on our bench, and chances are not bad that he'd still have a pretty reasonable season for us, maybe 5-8 goals frmo the subs bench which is better than any of our current strikers, but I'd personally rather he got a full season at, say, someone like Empoli, put in 15 goals, and show that he's really ready to take on a bigger role at Inter.
As I said, if he's our 'first substitute' goalscoring striker, then its a little bit of a different story, because both Thuram and Lautaro are streaky, and there he'd start to rack up decent game time, if he can translate his goalscoring form frmo B to A, then that would be quite an exciting role for him to fulfill. But I wouldnt want him to be 4th/5th choice striker at Inter, its a waste of talent for time being.
The U23 question is an interesting one, though I'd much prefer to give him development time at Serie A level, but it will depend on how the squad shapes up - if we have 3 strikers then maybe the U23 role is an interesting one, but if we have 4 or 5 then I'd rather not