Coming from a predominantly MTB perspective (I do ride road but not big miles and never ridden SRAM road groups to compare), SRAM and Shimano seem to leapfrog each other in terms of performance with successive generations. Looking at shifters and derailleurs at the XT/X9 performance level, in the early 2000s, Shimano had the edge, then mid 2000s to about 2010 SRAM, now Shimano are back on top. Other parts of the running gear each brand has different strengths.
As far as durability, I'm still running 2007 SRAM X9 shifters and derailleur on my FS MTB, and that bike has been through a ton of 'consumables' (at least 6 chains, 3 cassettes, a couple of sets of chainrings, rear wheel bearings, BBs a couple of fork and shock rebuilds). Anecdotally, XT stuff from the same era hasn't lasted as well, with shifters getting sloppy and crunchy and getting thrown out. Pre-shadow shimano RDs also stuck out like dogs balls and consequently tend to have been wrecked, though I've seen a fair few of both brands get mangled.
I haven't noted any suspicious difference in durability of the drivetrain parts - I run shimano cassettes cause they're cheaper, KMC chains likewise, Shimano cranks because XT is the best bang:buck there - light, stiff, cheap, best shifting out there. Older shimano alloy chainrings were made of soft cheese (maybe an alloy of gouda and and emmental, who knows

), newer ones are much better. Until 2012 model year, SRAM (Avid) hydros were consistently better performing and more reliable than Shimano, legend has it that 2012 brakes are great but I haven't ridden them.
What does this all mean for road levers? Who knows, maybe SRAM do have a fragile design. But if they were truly half as bad as the naysayers on here would have you believe, do you
really think SRAM would keep making them that way, selling them at low margin, and warrantying them as well as they are universally acknowledged to? Sounds like a way to lose money fast if you ask me, reminiscent of selling units at a loss and making up for it on volume.
I do like the Campy philosophy that all parts should be serviceable & replaceable, but it's unlikely to be a cost, time or hassle saver for many out there compared to getting a complete new unit under warranty
if things go bad. Few people ride enough to wear out a road shifter sooner than they would want to upgrade anyway, and fewer still of those would be confident or competent to diagnose a problem, take it apart, replace the part, and put it back together correctly. Unfortunately I suspect even few shop wrenches have the skills. Even when those ducks line up, what is going to get you back on the road faster & cheaper:
1 - Take bike back to shop, uninstall and take apart shifter, identify broken part, order replacement & wait days/weeks for it to be delivered (or install from shop stock if they carry full range of parts - ?likely?), reassemble & reinstall
2 - take bike back to shop, SRAM authorise replacement shifter from shop stock (or send out new shifter in days), uninstall old shifter, reinstall new shifter.