The fortresses around Liege at the start of WWI were supposedly state-of-the-art at the time, but were quickly destroyed as soon as heavy artillery was brought in. Superficially, the descriptions of the two fortifications sound similar. Did the Maginot line represent a dramatic improvement over the kind of fortifications around Liege? Or could a week of heavy artillery bombardment have neutralized the Maginot line as well?
I can't speak with any authority as to whether the Maginot Line could have been penetrated in x number of days by y amount of resources dedicated to said penetration, but I can say that the Maginot Line was constructed in a more dispersed fashion.
The Belgian fortifications in the 1910s had concentrated defensive structures that were more vulnerable to concentrated heavy artillery than the Maginot Line. The Maginot Line was designed to not be vulnerable to concentrated artillery bombardment. The places that would naturally draw the most fire were designed to resist it. Places where concentrated numbers of soldiers would be stationed were underground or built into natural terrain features like hills, there were many artillery pieces placed in retractable (into the ground) turrets, but the biggest difference was the design philosophy of having dispersed defensive positions, so there weren't natural targets for artillery to hone in on. The Maginot Line wasn't a wall, it was a 10+ mile deep line of defensive positions.