Same port with different standard. 25 watts could be lots of things. 5V, 5A or 9V, 2.78A or 12.5V, 2A which can be incompatible with current Power Delivery.You don’t have to buy it…
It will still be USB C
Remember the 29watts Apple's USB-C brick that's actually incompatible with Magsafe?

Apple’s old 29W chargers aren’t good enough for MagSafe Duo
It sounds like its 30W charger is the way to go
