Applicants may have to delay filing applications for citizenship until they have proof that they have filed their tax return. This could impact their ability to meet the eligibility requirement of physical presence.
On the other side, the requirement of physical residence and of intention to reside in Canada is narrowing the gap in most common cases between common terms and tax terms of immigrant and resident. However, based on the cases I saw already, more mistakes on tax filing to be seen due to the much more complexity of ITA.