Market forces will drive the folks that can't/refuse/are just too stupid out to adjust of business. Personally, I'm sick and tired of the paths being beaten to Toyota. Where's the Ford guy that can say "Do it right"? He's retired or working for Totoya. Don't forget, Totoya and Honda have been working up to their market positions for a long time.

 

Update: I took a careful look at my reservoir. Previously, I wrapped the neck with teflon tape and it did not melt. However, the teflon tape was soaked with brake fluid.

I looked at the seal surface of the reservoir and cannot see how it is malformed or a "defect". The ridge appears to be part of the molding or design. A soft gasket is designed to form itself to minor irregularities, and this ridge is just designed to further improve the sealing.

I think there are several things in common with the various fixes:

Using a rag stuffed in the reservoir to prevent plastic chips from falling in while smoothing out the neck. This may soak up or absorb some of the brake fluid in the reservoir.

Having the dealer swap reservoirs several times until one no longer leaked. It's possible the fill level was different, with the most recent reservoir not filled as much as the others resulting in the leak being fixed.

Lastly, the obvious solution is to remove some of the brake fluid from the reservoir.

There's a slit cut in the center of the gasket, and if the fill level is too high, some of the brake fluid can shoot right through this slit, onto the back of the gasket, and drains out through the cap. That's my theory at least.

A fix would be a revised cap gasket with a smaller slit, or the center piece located MUCH higher to prevent sloshing brake fluid from seeping through the slit.

 

My fix was to remove the cap, remove the gasket from the cap, make a washer out of an old inner tube, insert the inner tube washer in the cap, replace the gasket, replace the cap.

It's been 6 months and no more leak.