Bismillahi Al-Rahmani Al-Rahim
The position used for fatwa is that someone who does not pray because
and then refuses to pray (with slight differences between (1) and (2) in how this is determined) after being told to pray or face the consequences, is ruled to be an apostate and put to death. This entire sequence of events depends on the Caliph or someone authorized to act on his behalf.
Ibn Qudamah (may Allah be merciful with him) argues that people from category (2), those who simply are lazy or do not give much importance to the prayer, are not declared apostates. His opinion is similar to the mu`tamad in the Shafi`i madhhab. My Sheikh prefers this opinion, as do several other contemporary Hanbali scholars (may Allah protect them).
As for what you cite as Ibn Taymiyyah's position (may Allah be merciful with him), I really do not know whether or not this is how he formulated it.
And Allah knows best.
Wa al-salamu `alaykum,