True enough - but they've carried out multiple strikes with the SU-22s in their possession and can presumably restock / refit those with Iranian support -- they also have several dozen older MIGs. There's no doubt that they'd be annihilated if they tried to use those for continued offensive missions outside of the Yemeni borders but they could likely pull off a single fast attack on Cairo or Suez if they were so inspired.
I would view claims of "several dozen older MIGS" with great suspicion. There's a report of a single MIG-29, but no word of its flying condition. In the civil war, Yemen had to rely upon mercenary pilots to fly them, as well as maintain them.
> but they could likely pull off a single fast attack on Cairo or Suez if they were so inspired.
No. They couldn't. Yemen to either is like three times the range of the SU-22 on a shortest distance path, which would take them through Saudi Arabia and close enough for mistakes of intent to Israel, either of which—as well as Egypt—has Air Forces more than capable of intercepting and destroying them if they magically gained the range to try to pull of that kind of flight.
The Houthi Air Force is useful for their civil war, and not a whole lot else.