This really isn't the case though.
The PIC18F - which currently only support SSLv3 and below with weak ciphers - is ~£1.75 in bulk. An ARM Cortex-M3 that costs the same, has more functonality and more flash can support TLSv1.2 with good ciphers.
Time and time again I see people saying "but the hardware can't do it". It's perfectly possible to design your hardware to the same cost and have the functionality required.