VHF wavelengths range from 1 meter to 10 meters. It is not possible to fit onto an interceptor or a SAM an antenna sensitive enough to these wavelengths to determine the direction of the signal with enough accuracy to guide an interception. So, although your VHF antennas on the ground might be able to tell you that there are warplanes in your skies, when you send up your interceptor aircraft or SAM, it is blind to the F-35s or blind enough not to represent much of a threat to it.
The F-35 is the US's fourth major stealth warplane. It was chosen because the Pentagon was happy with the first three, particularly the B-2. The Pentagon has chosen a fifth stealth warplane, the B-21 Raider, which has the same basic shape and mission as the B-2 (but weighs about half as much).
At a lot has changed post P-18 Serbia. VHF and high power L-band ground search and also guidance radar tech of RU and CN are the real threats and they aren't being adequately addressed in either SEAD or first-strike capabilities.
F-117A has a tiny payload and relatively large RCS in VHF. The B-2 RAM can't handle moisture and overall isn't easily upgraded. F-22 doesn't meet RCS RFP requirements in any abeam aspect in any band, only frontal; it has 90's avionics; it's hard to make more of them; and LO maintainers at Tyndall are constantly busy repairing crumbling RAM. LRS-B isn't really IOC, Super Raptor is still fragmented and experimental, and "F-47" is still complete vaporware. Fat Amy isn't as good as the West believes it is against modern, real ground-based search and guidance radar tech of RU and CN.
https://www.globalsecurity.org/military/world/russia/radar-r... https://archive.ph/f0fxZ
https://www.globalsecurity.org/military/world/china/radar.ht... https://archive.ph/wMhDf
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Radar attenuation and RCS of sixth-ist gen fighters in different radar bands:
https://basicsaboutaerodynamicsandavionics.wordpress.com/202...
The touted NG replacement Growler pod ALQ-249 doesn't even touch VHF.