I mean, isn't this exactly how reaching 5% was proposed for most NATO nations? AFAIK, the intention was to spend 3.5% directly on the armed forces and spend 1.5% on infrastructure critical to national security. Those combined would give the 5% mentioned in the article. This isn't just an idea from Starmer, it's an idea from NATO allies.
As to the other thing, I'd argue that China have been a responsible nuclear power. I mean, what have they done that other nuclear have not to challenge that status? You could suggest that the procurement of nuclear-capable effectors is irresponsible, but both France and the US are doing the same, and the UK is at least considering it.
I'm loath to trust the Telegraph on either of these issues.