... public transport infrastructure that is desperately needed but in all likelihood won't even begin construction for 8 years and won't open for 15-20 years?

The Bakerloo Line extension plan will begin construction in the early to mid 2020's to finally connect South East London to the tube network.

I believe strongly that London needs more transport infrastructure, the tube is over capacity and so are all the commuter train lines into London terminii, but it's hard to get hyped about things that will open when you are in your 40's. Especially as Crossrail, the very expensive transport infrastructure project that will be opening in the next few years is connecting already the already connected West London to Central London and then going to a few of the areas in the North and East already on a line.

Only 7 of the over 200 stations on the TfL Map are in South East London, it's woefully under served and so frustrating that it will only get a bit more connected in in the 2030s and even then all tube stations will be on the site of existing train stations.