Hello I might have solved the issue in some way.
Short story, it wasn't working so I manually changed the settings on the engine_config.txt file (C:\Users\Username\Documents\Mount and Blade II Bannerlord\Configs). I didn't do a proper test for each config, just turned off most of the fancy stuff, reduced max FPS to 75 to match my monitor and left the most common and basic ones like AA and Texture stuff untouched. And BAM finally went trough the brightness screen, didn't have time to play, so just made sure it didn't crash on the first scene (the training grounds?) and quit without any issue at all.
Despite not being certain if it was the fps change or some other setting what fixed the issue for me, I'd like to suggest that maybe the default configuration being lower could help avoid this. I'm aware it wouldn't fix the source of the issue, but it would be better for users if they can at least access the settings in game before the game encounter any issues, so they have an user friendly way to adjust settings instead of having to find the config file.
Not sure if it'll help because maybe the game changed something after I got in, but this is how my file looks.
umber_of_ragdolls = 5
max_simultaneous_sound_event_count = 1
invert_mouse = 0
foliage_quality = 4
decal_quality = 4
texture_filtering = 5
graphics_adapter = 0
first_time = 0
brightness_calibrated = 2
texture_budget = 3
texture_quality = 4
show_framerate = 0
max_framerate = 75
cheat_mode = 0
water_quality = 2
display_width = 1920
display_height = 1080
display_mode = 1
selected_monitor = 0
force_vsync = 1
enable_cloth_simulation = 1
enable_flora_sway = 1
shader_quality = 2
postfx_dof = 1
postfx_sssss = 0
postfx_ssr = 0
postfx_bloom = 0
postfx_sunshafts = 0
postfx_streaks = 0
postfx_hexagon_vignette = 0
postfx_vignette = 0
postfx_grain = 0
postfx_lens_flares = 0
postfx_chromatic_aberration = 0
postfx_motion_blur = 0
tesselation = 0
particle_quality = 1
particle_detail = 1
terrain_quality = 2
shadowmap_type = 2
shadowmap_filtering = 1
shadowmap_resolution = 3
disable_sound = 0
sound_device = 0
sound_output = 0
resolution_scale = 100
enable_dynamic_resolution_scale = 0
dynamic_resolution_fps_target = 60
lighting_quality = 1
antialiasing_technique = 4
environment_detail = 1
character_detail = 4
safely_exited = 1
enable_controller_vibration = 1
weapon_trail_amount = 0.5000
display_refresh_rate = 60.0000
master_volume = 1.0000
music_volume = 1.0000
sound_volume = 1.0000
mouse_sensitivity_coefficient = 0.5000
gamma = 2.0000
sharpen_amount = 0.0000
control_mouse_movement_y_scale = 1.5000
control_mouse_movement_max_accumulation = 40.0000
control_mouse_movement_accumulation_decay_speed = 100.0000
brightness = 0.0000
brightness_min = -0.0060
brightness_max = 1.0060
exposure_compensation = 0.0139
antialiasing_technique = 4
occlusion_technique = 1
Gonna try to have some fun this weekend on the game thx and best wishes for you
.