What does the "incur $230 million in charges" mean? Why would it cost them money to lay people off and have less office space?

Possibly a bad LLM edit; maybe they meant to say would save $230 million through reduced headcount and less office space?

One time charges are pretty typical when layoffs are announced. They are usually the cost of severance pay for the weeks or months of salary paid to employees who are no longer working. Office space leases are typically long term (multiple years) and accounting rules require they recognize the expected future cost of that now-useless space when the layoff decision is made. In practice, cash won't actually change hands for the office space until rent is due in future months. And companies will work with the landlord to get out of the lease (but often pay some penalty for the privilege).

Also, please note that maybe not all employees on this layoff are US-based.

In several countries, laying off people come with legal requirements for mandatory minimal severance, health insurance extensions, legal taxes and government fees and all kind of compensatory one-time payments for the fired employeer.

Usually layoffs have a one-time charge associated with closures and severance and other such payments (COBRA?).

But $230 million over 1,600 is $145k per person.

Possibly not. Buying yourself out of employment and commercial rental contracts can give rise to costs.

In the UK, statutory redundancy pay, after 2 years of service, is 1 week of pay per year of service and 1.5 weeks if you're over 41.

For a long duration commercial lease it might be worth paying to break the contract rather than the running costs for an unused building.

These are probably short-term costs, with longer term savings projected from the reduction in headcount and premises.

"Charges" are severance and related benefits. If they have to close offices, they may have to break leases, etc.

A charitable take would be that some of that is attributable to benefits packages to help the people transition to new work?

It's the severance cost, mostly.

possibly the spending required to do all the severances