The TMC2240 has temperature monitoring, the downside it that it only sends temperature data when the motors are enabled.
Which for temperature monitoring of the drivers, is satisfactory.
Here is a PR from mainline Klipper with some of the discussion:
Klipper3d/klipper#6210
TLDR; Mainline Dev's dont want to add it, as it would be a "special snowflake" since no other sensor is allowed to send a "null" value.
It would be great to control cooling for the drivers directly, without adding additional temperature probes.