Why is it important to keep lead lengths short for components used in circuits for VHF and above?
Why Any straight wire has inductance, roughly 20 nanohenries per inch, and inductive reactance grows with frequency (XL = 2πfL). At HF that stray inductance is negligible, but at VHF and above a half-inch lead can add tens of ohms of reactance, detuning tuned circuits, adding unwanted series impedance to bypass capacitors, and turning leads into small radiators. Keeping leads short keeps that stray inductance, and the reactance it produces, as small as possible.
Watch out Thermal time constant and component lifetime are heat-related concerns tied to the part's mass and dissipation, not to RF behavior, so the choice that lumps everything together is wrong too.
Short leads = less stray L. XL = 2πfL, and at VHF the f is big, so even 20 nH per inch matters.