Burn-in only usually happens when you're sitting on a static image for a very lengthy amount of time. Thus, you're not going to get burn-in with an OLED TV, especially a G5, unless you're just sitting in one BF6 lobby for like 8+ hours a day for weeks on end, never dying and the lobby never closing.
Since BF6 cuts off the HUD when you die, and when you finish a game, and you're probably using that TV for other forms of media, that means burn-in is entirely unlikely to happen. Rtings also has a test about this:
Long periods of static content have resulted in some permanent burn-in (see the CNN TVs); however, the other TVs with more varied content don't yet have noticeable uniformity issues on normal content. As a result, we don't expect most people who watch varied content without static areas to experience burn-in issues with an OLED TV.
For example, someone who plays Call of Duty or another video game without bright static areas for two hours per day may expect similar results after about 2500 days of usage. It corresponds to about seven years.