Yep Beach Rd is only way in for the Matty beach. As Jim mentioned you do need an annual beach pass. Right now you'll also need 4x4 at a minimum and I would take some tools to get yourself unstuck. Tides are coming up and water is higher pushing traffic up into the soft stuff. That combined with the lack of rain and the sand is really soft. I've seen numerous Jeeps, Tacomas, etc. stuck on this beach.
Fisherman1ATX fishes this beach some.
https://texasfishingforum.com/forum...r-great-fishing-trip-in-matagorda#UNREAD