IBM Thinkpad t43p was my first heavy duty laptop. In 2005 IBM made a mistake that someone in their management must regret to date, selling Thinkpad laptop line to Lenovo. Things went downhill for Thinkpads and I lasted 3-4 more generations before finally giving up. Thinkpad had a shot at being the world's most loved laptop, by developers and businessman on the go. Passion for great products and great user experience…
Thinkpads were actually manufactured by Lenovo right from the start, they were only badged by IBM. But even then, why should anyone at IBM care what happened to the brand after they sold it? I know some creators love their product lines and such and care about posterity, but, IBM!
Even then it's like saying iPhones manufactured by Foxconn are only badged by Apple. The original IBM Thinkpads all the way up to the T43 were developed by IBM and built/designed significantly better than the ones today. Also a large selling point of the old models was the software (!), which made some things easier.