FWIW, I got EXP from Barclay CC spend. They gave me a generous limit and I was able to get EXP between Dec and Mar to qualify under the new system. In his case, I'd suggest heavy spend in the first statement month that ends in January so the spend counts towards 2023.

If he flies on award tickets, Upgrades are possible on award tickets with EXP. I even get upgrades on award tickets from BA points after adding the AA FF# to the record.

In general, I've found Barclay easier to deal with than Citi for personal cards but can't say on business.

The worth it question depends on his flight routes. It's great for my DFW-ABQ runs.