What's the point of him saying anything? What will it achieve?
It won't benefit the UK, the people that dislike him will still dislike him, and it won't make the US return the dictator to Venezuela.
All it would do is prompt the orange baby to economically cripple the UK in childish retaliation. That means mass unemployment. It means failing public services. It means worse job prospects. It means a worse life for all of us.
I may not like it, but diplomacy is about picking your battles, and this one is a stupid hill to die on. There's a reason virtually no leader has kicked off about this.
The pragmatic thing to do is keep quiet about the US while simultaneously quietly building a closer relationship with Europe so that in the future we're less affected by US bullshit, and that seems to be exactly what Starmer is doing.