This is about smoking tobacco

Not exclusively. Please re-read the article and then familiarise yourself with the bill, particularly the following excerpts are relevant:

From the government: https://www.gov.uk/government/news/smoking-ban-introduced-to-protect-children-and-most-vulnerable

Subject to consultation, the government is considering extending restrictions in places that are currently smoke free to also become vape free, especially in areas where there are children and young adults.

(Emphasis mine)

This may sound reasonable, but surely the issue of e.g. a child vaping outside of a school is covered by the fact they shouldn't be vaping as a child anywhere, and thus would either have the vape confiscated by parents taking them home or school staff? Is it currently a large problem of adults vaping outside of schools? Who would do this specifically? Such regulation placed on adults seems just unnecessary.

Unless of course: it's not actually about the children as it tends to be with Murdoch newspaper moral panic-steered policy and is instead a much broader attack on vaping as a culture war issue, which is supported by the broad far less "reasonable" powers granted by this bill as per below:

This sits alongside a ban in the Bill on vape advertising and sponsorship, as well as powers to restrict the flavours, display and packaging of all types of vapes, as well as other nicotine products.

As you can see, your statement

Disposable vapes will be banned. That’s it.

Is flat-out untrue. This is by far not the extent of it clearly.

If I cared to speculate I'd say this is an attempt to win back the elderly vote after the winter fuel payments turned off a lot of those voters.

Probably you do so because you got your fodder in the Murdoch papers and just need to regurgitate your breakfast. Judging by the lingo.

I'm really very sorry, and I do not want to embarrass you, but it appears you're referring to yourself there. It's okay. No one is immune to propaganda and we cannot all dive deep on all topics all the time.