alt Hacker Newsthey didn't get the telemetry after, what it was, 16 min(?) hope they'll find the reason which will be hard without black boxes like on airplanes. as every engineer knows it works flawlessly only at the end. if ever.
the booster was the same, great, but not surprising.
IIRC they had 30 cameras on board & who knows how many sensors (probably hudreds ?).
So even if an engine bay fire burned the electronics and interrupted all coms (or FTS blew it up) they should already have a lot of data by that point showing how it went wrong.