It certainly makes sense that such a hardware change slows things down a bit, but USB-C phones have been on the market since 2015 and pretty much standard since not long after that. If I want a USB-C powerbank or flash drive, I pretty much have to buy it online and I'll likely pay a premium for it. If some newly-introduced device in 2019 uses a USB connector to charge its integrated battery (a misfeature in itself if you ask me), it's almost never USB-C.
In short, I don't expect existing product lines to get revised, I expected to see USB-C show up faster on new products that aren't phones or tablets.