Actually I have read and heard that LCD is brighter than OLED
https://www.cnet.com/how-to/led-lcd-vs-oled/
Extract:
Light output (brightness)
Winner: LCD
Loser: OLED
Take this category with a grain of salt. Both TV types are very bright and can look good in even a sunny room, let alone more moderate indoor lighting situations or the dark rooms that make TV images look their best. When it comes down to it, no modern TV could ever be considered "dim."
LCD gets the nod here specifically because the whole screen can be brighter, a function of its backlight. OLED can't do a full screen with as much brightness. Full-screen brightness isn't very important in the real world however, so this category is a relatively hollow victory for LCD.
Light output also plays a big part in High Dynamic Range (HDR), which we'll discuss a little later.
And here:
https://www.digitaltrends.com/home-theater/oled-vs-led/
Extract:
Brightness
When it comes to brightness, LED TVs have a considerable advantage. LEDs were already good at getting extremely bright, but the addition of quantum dots allows them to get even brighter. OLED TVs can get pretty bright, too, and with such dark blacks, contrast between the brightest and darkest spots on screen is all the more exaggerated. However, cranking OLED pixels to their maximum brightness for extended periods not only reduces their lifespan, but the pixel also takes slightly longer to return to total black.
With those considerations in mind, it’s important to note that all modern TVs — OLED, LED/LCD, or otherwise — produce more than adequate brightness. The consideration then becomes where the TV will be used. In a dark room, an OLED TV is going to perform best, while LED TVs will outshine them (quite literally) in more brightly lit environments.
It should also be noted that Sony introduced some incredibly bright OLED models in 2018, and LG’s next-gen OLEDs are also impressively bright, making them perfectly suitable for nearly any situation, save direct sunlight beaming onto the screen. Still, when compared directly, LED still has the edge.
Winner by a nose: LED/LCD