Phoenix and Cyber Angel are the best counters to GB. Ninjas and Ancient Gear can sometimes be problematic depending on the hand. Burn and stall decks get destroyed by GB.
"A good glad deck is a hard counter for cybers. Cybers lose the matchup 9 out of 10 times." -> So my deck is bad against them. I lost 4/4 duels against CA decks.
what you do is after they are done you econ take during your turn so not only do you survive with another monster on your field but you can activate their effect adnd clear their side of the field
AG with Gravity Blaster works well, even if attacked in defense mode the cards will go into the deck. Another good tech card is 4 Star ladybug of doom, which will destroy most of their GBs except maybe Murmillo.
I run my choas Frognarch deck with 3 treeborns, 3 DMoC, 3 Angmar, 3 Screech, 2 Fanguang, 3 soul exchange, and 3 econ. As long as I get a frog into the circulation, i can just continue to use my opponents monsters as tributes via econ take and soul exchange. They either quit or run out of resources.