They originally invested in the webview interface. In light of that investment, doesnt that mean its a good idea?

No, of course not. What they invest in is irrelevant. Only results matter.

Just look at Mootothemax's comment further down the thread. Poor UI wasn't causing people to not use FB.

Valley execs are probably the most susceptible group to falling in line with the echo chamber. Currently the chamber is reverberating with 'APPLE GOOD!'.