This analysis matches my experiences with both kinds of devices. I am writing this on a T60, which is also from 2006 as the laptop of the author. It is a device I use regularly (I prefer the haptics of it over newer ones, especially when writing), but not as my only daily driver. The main stop gaps are video streaming sites. For those I have an X220, which has no problems at all with “modern” websites". Both run a “minimalist” Linux distribution (Bunsenlabs).

Moving towards newer Thinkpads has the downside that the article already mentions: the design quality of Lenovo’s Thinkpads did a sharp downturn between the x220 and 230 series and seems to recover only temporarily. One problem that the users of an X60 or T60 face, is that both are still 32bit systems, which will lead to increasing incompatibility of software. Going for a X61 or T61 can solve that problem.