It doesn't matter how bright the source is, if they're pointed in the right direction.
Speaking from a concert-lighting / color theory / lighting design background here...
Any light, as you look at it from the outside, you should see the reflection of the light source, and not the light source itself. If you are seeing the source itself (i.e. "bulb"), that light is not aimed/pointed/'focused' where it needs to be, it is simply projecting light in ALL directions - which is what blinds you. When you see the reflection, you are seeing light coming from the source, and being bounced in a particular direction - i.e. where it belongs, and not blinding you.
Sealed beam lights suck. They are candles compared to modern lights.
Halogen conversions are great for our classics - they still have the serrated ("fresnel") lens design so they look right when off, but you get a replaceable bulb inside that is multiple times brighter. I use Hella sealed beam conversion lights on anything (car or motorcycle) that originally had sealed beam lights - they make them in 5.75" and 7" round, 4x6 and 5x7 rectangle, and I prefer the E-code (European), because they have a better beam spread down the road.
The next step above halogen is HID - High Intensity Discharge. Very low amp draw, they only pull heavy power during startup. They have a ballast that turns 12vDC into something on the order of 10,000vAC. The light you see isn't a filament that glows, like a sealed beam, incandescent, or halogen light, but is actually a miniature bolt of lightning inside the capsule (glass part). They are not instant-on - they have to ignite, and "warm up", which can produce a delay compared to other lighting types. You can get different colors in these - they change the gas content inside the capsule to get different colors. People love the blue lights, which is stupid - blue light is the color spectrum the human eye sees the least. Color is measured on a Kelvin scale. Numbers I know off the top of my head are 3000k (kelvin) for an amber/fog light bulb; 5300k daylight white for normal use; 6000k is starting to go blue. There are 2 types of HID housings - one, is bulb-replacement HIDs that you can use in halogen housings. Pull out the halogen bulb, install the HID bulb, wire up the ballast, and you have more light, same beam pattern, and less electrical draw. I run these in the low beams of my Charger, as well as in the hi/lo lights of my minivan, and most of my motorcycles. There is also a projector-style HID that is OEM on many cars nowadays - this is a bulb, at the back of a projector-type lens that has shutters inside. When you turn on high beams, the shutter opens and the spread of the beam gets taller. Not brighter, just taller.
The newest lighting development is, of course, LED. Insanely low power draw, nearly infinite power capabilities, and the ability to configure literally ANY shape or design into the vehicle appearance and get adequate forward lighting. Factory LEDs contain heated lenses, because LEDs don't create any heat to de-ice in wintertime; aftermarket LEDs do NOT (unless noted on their particular package). You can get LED replacement bulbs for any halogen housing if you want, but I have found they put the actual source (the placement of the "filament", if you will) in the wrong location relative to the reflector, and you get odd beam spread patterns because of it. You can get LED replacement housings like I have in my Wrangler, which contain high-output LEDs mounted to a position where they project onto the reflector, and the reflector focuses the light down the road for you. There are LED replacement bulbs that look like a bees honeycomb, full of led's pointed right out at you - THOSE, will blind anyone unfortunate enough to be in front of them, and the majority of them are NOT DOT approved for that very reason. They simply blast light "that direction", with zero focus or discretion. LEDs can also be had in any color - I run 3000k (amber) LED high beams in my sealed beam conversion housings, in my Charger (to go with my 5300k HID low beams). In my Ram, I have 35w HID low beams and LED high beams, all in 5300k daylight white, in the factory Sport headlight housings. LEDs are instantaneous, so they make great high beam units.
But ALL of my lighting - even if it is bright enough to go half a mile down the road - is pointed in the right direction. Nobody flashes me to tell me they're too bright. Ever. I can cook a deer where it stands...but other cars have zero problems with me. THAT, is the key. Use the right style bulb, and point the lights in the right direction. Biggest culprits around here are the LED's that look like honeycomb - they're cheap, but they suck - and people who get "leveling kits" on their trucks and don't adjust accordingly afterwards.
I live in deer country. I put as much light as I can get on my vehicles, so yes, the bright bulbs CAN be "necessary" - but again, you have to use the correct design, and you have to point them properly.
