Leading link vs. telescopic forks

[Puffs]

With a friend of mine, we were discussing the merits of leading link forks, like on the ES, and several other older bikes. 'Older' is the relevant word here, as it appears that very few bikes with leading link forks are still produced nowadays; it's all telescopic forks.

A prime merit of the leading link design is more lateral strength, which is what you need with a sidecar. This is why all MX sidecar outfits have it.

Personally I have little experience with a bike with leading link forks. I only once had a Honda P50, which had very basic leading link forks (no decent shock), and was poorly balanced. This caused the front of the thing to come up when you applied the front brake. Yes up, not down as is normal with telescopic forks.
And therein lies one of the issues of telescopic forks: on hard braking, the front dives, and the forks loose all sort of effective suspension. Because then the fork is more or less at the end of its travel.

By contrast, a well balanced leading link fork should not dive (as I understand the ES does indeed not), and has the potential to continue to provide a fully functional suspension unit, also under hard braking.

Another issue with telescopic forks is that you're combining 2 different requirements: you want it stable sideways, but still want it to move in & out smoothly. Over time, those bushes & stanchions wear, and seals start to leak.

To frame it, a pic of an ES:

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So my question is: Why has the leading link design been largely abandoned?

[Blurredman]

In the world of being unable to use/source precise engineering to develope and produce reliably consistent (and non wearing) telescopic forks even if it may or may not have been cheaper producing leading link forks it was certainly simpler and quicker in construction for the purposes of getting bikes off the production line?

[Puffs]

Yeah, leading link forks should be easier to produce at consistent quality. Telescopic forks require good hard-chromed stanchions, suitable sliding bushes (ideally w/ Teflon), seals, ... Well, a good telescopic fork is just a lot more complicated. Of course that does not apply to the forks in a £99 MTB from Halfords.

There's been quite some development in (front) suspension over the years, starting off from the girder fork. The earlier models were, well, just quite simple to make, I guess. But 'more complicated' does not necessarily mean 'better', IMO, and I still feel that a leading link fork might bring advantages over the currently leading telescopic design - but does it?

My experience with the P50 was pretty poor, but that was a very cheap implementation, on par with said fork in a £99 Halfords MTB. But how do you like the fork in the ES, how does it perform under braking (as well as that SLS does)? Can anyone else share experience with a decent leading link fork (as also found in the earlier BMWs)?