Getting a IR lock might be challenging on a hot day, and it's probably not very big on a radar. Imaging sensors and, hell, sound, would both be useful for targeting.

Hitting anything at altitude and moving with small arms is a waste of ammo almost all the time. You would need big energy (7.62 NATO or above) plus a little mount with a tracking system plus precision servos, all locked down on something that doesn't move much. It's a lot of kit to carry around.

But, regardless, that thing is dead meat. Electric drive drones everywhere today means AA platforms like Gepard/Cheetah, ZSUs, and similar have returned to the battlefield in force.

Those rapid fire cannons . . ok, basically, explosive shells and soft skinned vehicles like this are a terrible combination, due to how detonations affect flexy materials like this.

We saw this in WW2, when the otherwise-incredibly-durable[1] soft-skinned Wellington bombers and Hurricanes started eating cannon shells from new mods of fighters. The brisance of the explosive shells did a tremendous amount of damage, which sucked, because the Wimpy was frickin' awesome, IMO the most successful medium (but kinda heavy) bomber design of the war. Metal-skinned aircraft still got shredded, but the damage was a lot less - like a LOT a lot, it's hard to overstate what it did to the geodetic frame on a Wimpy - and frag didn't go as far.

[1] Wellingtons could eat infinity bullets, as even if they knocked out a strut, it's a geodetic structure - there's thousands more struts to go, and they share the load. Cannon rounds . . ah, sad Wimpy trumpet sounds