There generally is no ‘immediately’ when it comes to disabling warp.
The game works in server ticks and the earliest they could disable your warp is after a number of ticks it takes to lock your ship.
The only way to immediately disable your warp is if you’re inside a warp bubble. You were caught in low sec (Miroitem), which is not corrupted by faction warfare at the time so a warp disruption bubble is not allowed there.
That leaves us the question how you got caught by that solo Gnosis.
The Gnosis fit that caught you was this (I found a loss of your killer):
[Gnosis, Gatecamp Gnosis]
Damage Control II
Gyrostabilizer II
Reinforced Bulkheads II
Reinforced Bulkheads II
Reinforced Bulkheads II
Tracking Enhancer II
50MN Y-T8 Compact Microwarpdrive
Fleeting Compact Stasis Webifier
Warp Disruptor II
Sensor Booster II, Scan Resolution Script
Sensor Booster II, Scan Resolution Script
Sensor Booster II, Scan Resolution Script
425mm AutoCannon II, Barrage M
425mm AutoCannon II, Barrage M
425mm AutoCannon II, Barrage M
425mm AutoCannon II, Barrage M
425mm AutoCannon II, Barrage M
Information Command Burst II, Sensor Optimization Charge
Medium Targeting System Subcontroller I
Medium Targeting System Subcontroller I
Medium Transverse Bulkhead I
‘Integrated’ Hobgoblin x2
Hornet II x3
And has 1329 sensor strength at max skills, which should lock your Anathema after about 1.4 seconds. (Or 0.7 seconds if your MWD is on, so don’t do that!)
It is fast enough to tackle your uncloaked Anathema before it warps within three seconds, but a sensor strength like this is by far not enough to catch ships that warp within two seconds.
It should not be able to lock your Anathema if the Anathema is cloaked already at the first tick after you start aligning.
So what happened here?
Did you not cloak immediately? Did something block your cloak?
The center of an Electric Metaliminal storm could block the usage of cloaks, but I currently don’t see any metaliminal storms anywhere near Miroitem so they cannot have been there either four hours ago.
Did the Gnosis pilot have containers or drones scattered around the gate that you were within 2km of? That would block you from cloaking and stop you from warping.
If you see that happen, it could be a good idea to instead make a run back to the gate. If they aggress you they cannot follow you back through so if you make it to the gate you’re safe.
If you didn’t see that happen, are you sure your overview shows containers, drones and other decloak objects? It might be they were there but you simply didn’t see it.
I recommend always having the ‘show all brackets’ option for the overview. It doesn’t put all objects on your overview itself, but makes objects visible in space so you know you’re near anything while flying a cloaked ship.
But long story short, it did not happen ‘immediately’, locking you took two or three seconds during which things went wrong you could have handled differently.