Ron Amadeo, writing for Ars Technica:

Google’s Pixel 3 smartphone is shipping out to the masses, and people hoping to take advantage of the new Qi wireless charging capabilities have run into a big surprise. For some unexplained reason, Google is locking out third-party Qi chargers from reaching the highest charging speeds on the Pixel 3. Third-party chargers are capped to a pokey 5W charging speed. If you want 10 watts of wireless charging, Google hopes you will invest in its outrageously priced Pixel Stand, which is $79 […]

Google got back to us. The Pixel 3 does not support 10W Qi charging at all. It supports 10W wireless charging, and it supports the Qi wireless charging standard, but these are two different things. Qi is capped at 5W, and for 10W wireless charging, you need a charger with what Belkin calls “Google’s 10W proprietary wireless charging technology.”

This is something I expected Apple to do, when they first introduced inductive charging, not Google.