The only time I really remember transistors being a red flag (other than early Germaniums) were some small Hitachi signal transistors from the 70s-80s - the TO-92 ones with the beveled top. Those things would go leaky or open or intermittent (their choice). It got to the point back then that I just automatically changed them whenever I saw one in anything I worked on.
** You talking about the the dreaded " black leg corrosion" problem ?
TO92s and the like with silver plated leads.
Silver sulphide would form on the plating, travel into the device and eat the chip.
Always Jap stuff like Marantz.