Streaming Airline Data alternatives

Good evening all!

This is my first post on this forum. I love this topic (aviation communications) and am excited to see responses from the masses on this

My subject is the ability to stream aircraft diagnostics information. Many aircraft manufacturers are attempting this (e.g. Boeing with AHM, Airbus with AiRTHM, Etc...). These companies lean heavily on the already expensive SATCOM, and/or ACARS VHF-based infrastructure. I know black box streaming has been a topic of interest on this forum, so apologies if already addressed. My questions to you all are:

1) How much is the industry paying for these services? (e.g. Boeings AHM, Airbus' AiRTHM, Embrear's AHEAD-PRO, etc.)
2) It seems costly (i.e. AHM services and ACARS reliance) and archaic that the industry still utilizes VHF-based systems..any thoughts on this??
3) Are these services reliable? Looking at MH-370 it seems not so much...
4) Any plans on modernizing this system??? especially with regards to the means in which the information is sent. Yes, I know about Flyght Aerospace and the cost restrictions to it...

Thanks so much for the responses! looking forward to the replies :-)

Regards,

-ritcheyb123