No surprises here. Just like the lockdown on iPhone screen and part replacements, Macbooks suffer from the same Apple’s anti-repair and anti-consumer bullshit. Battery glued, ssd soldered in and can’t even swap parts with other official parts. 6000$ laptop and you don’t even own it.
Non-soldered CPUs basically have not been a thing since a decade, and only the most niche maker Framework has something resembling that today. That is less on Lenovo and more on how the “slim” trend has gone for laptop industry as a whole.
I have noticed the soldered RAM in the E/L serie, but did not know T has that now. But I think the general essence of a ThinkPad with user repairability and durability is retained even now, with even the base E serie since E480 having MILSPEC certification. Great ThinkPads are simply more expensive, and any ThinkPad you get will be way better than consumer grade laptops, which I think has merit.