Better than equal. Most Blackjack is -0.6% EV playing basic strategy, but with counting, each true count is an extra ~0.5% of EV, leading to big betting on high count hands with EV of 1-3%. Of course, that's why casinos kick out counters. They're literally "too good" at the game, and they don't want that.

6 decks, as opposed to 1 or 2, does make counting less accurate. But ultimately everything I said previously applies. Those stats are based on the current common game of 3-2 Blackjack, H17, 6-deck shoe, no continuous shuffle, and double after split.

Counting works but the way to profit from it is easily detected. You have to bet big when the count is favorable, and a casino will see that and stop you.

The MIT Blackjack Team beat this, with the strategy to have one player at the table who would bet small while counting cards, incurring the expected slight losses to the house edge, and signal a teammate to jump in and bet big (like $5k per hand) when the count was favorable. Casinos now know to stop this - if you walk up to a table and want to bet big, they will require you to wait for the next reshuffle (or just reshuffle immediately.)