the normal content is too easy

[Illmaeran]

The game is not easy, every long time player just became a bit better.

There is also the usual scaling problem in Low Level content due to power creep, but that's still the same since I started in SB.
Yes, you can queue in for leveling roulett without a healer and clear ist, but that was already possible in SHB and SB.

The best example that the game is not becoming easier is the alliance raid. Just compare a CT one with the HW.
Both are "old" content but the difference in difficulty is huge.

But still, you hear horror story's about the CT.

You're 100% on point. My FC had difficulty with CT raids back when they were current content. It was the same for all raids and even many dungeons (looking at you HW) when they were current. These days, going back I've found them to be a lot easier and realized I'd simply improved over time. Having to deal with multiple mechanics coming in quick succession in EW content especially has made me more aware of things and helped me deal with mechanics that would have blitzed me back in the day.

Power creep and scaling mechanics make it a lot more forgiving, but we still need to pay attention to mechanics, avoidance, and healing/damage to get through them smoothly.

Absolutely, the HW were a big step up in difficulty and the SB and ShB alliance raids were an even bigger step up. Given the number of people I see die in them, it's clear they're all still challenging for people who haven't run them tens or hundreds of times. Anything will get easier, perhaps even boring, once you've done it a lot. That's the textbook definition of having a raid on Farm; the group has it down so well that it takes little to no effort to clear.

Let me know when that happens. Because I’m still positioning, dodging aoes, cleansing debuffs, keeping the tank alive, saving the run as PLD, and so much more after three and a half years and almost 5800 hours.

Indeed!