Tactical nukes are meant to take out poorly protected targets whose position is only approximately known, or heavily reinforced targets whose positions are precisely known. They can be used against widely dispersed infantry formations or tank battalions, surface ships or submersibles, aircraft, or even squadrons of aircraft. Detonated high in the air, they can set fire to a small town, or close to the ground, knock out an underground bunker. I imagine there are many different specialized munitions available for different applications. I know there are rocket-propelled nuclear depth charges and anti-aircraft missiles, we had both on my ship back in the 60s.

It depends on the nature of the target, how spread out it is over the ground, and how well protected it is, as well as how precisely known its position is. My guess is this facility was either a plutonium production reactor or a uranium enrichment centrifuge farm, or perhaps a munitions warehouse or depot of some kind. It might be comparable to any industrial buiulding, so a nuke would not have been necessary, or even particularly advantageous.

However, a heavily fortified structure, designed to withstand conventional bombs, or a heavy containment vessel, or an underground facility reinforced with rebar and concrete might require a direct hit with something more substantial, unless it was hit before construction was completed.

Knowing nothing about this particular case other than what I've picked up from the media, my guess is some precision-guided conventional munitions were probably enough. The clean appearance of the site in the "after" imagery suggests the rubble was hauled away to confound post-attack damage assessment and to hide any incriminating evidence which might have survived the attack. However, this does not necessarily mean the raid was successful. The Syrians are smart enough to do this even if the wrong building was hit, after all, you don't want your foes to try again, do you? They might get lucky the second time.

Careful examination of the imagery shows differences in color and texture on the ground, but these may be the result of different illumination or processing. It's difficult to tell without all the raw data.