On: Taxing Uber and Lyft rides is L.A's latest plan to...

[sbov]

No need to use the 1000x number, there's actually information about this out there, at least when it comes to greenhouse gasses. In 2016:

https://nepis.epa.gov/Exe/ZyPDF.cgi?Dockey=P100USI5.pdf

Medium and Heavy duty trucks: 425 Tg CO2

Light-Duty Vehicles (passenger cars + SUVs, pickup trucks, etc): 1,106 Tg CO2