The Filioque does have a dogmatic status in the West, to be sure. But Toledo was a local Council only - Rome’s Popes refused to add the Filioque to the Nicene Creed until later.
And yet, this is the interesting thing, the existence of the Filioque in the Latin version beginning in 1014 did not lead to any schism at that time.
We can even say with a good deal of certainty that the excommunications hurled by West and East at each other in 1054 were not “church-wide” but only “personal” between the papal emissary Cardinal Humbertus and the Patriarch Cerularios. In fact, there are testimonies that East and West considered themselves on Church until at least 1200.
There is at least that precedent to confirm that the Latin West’s use of the Filioque did not mean it was automatically in conflict with the East and that the East, although considering it an aberration, did not shout “heretics!” at the Latins for so doing.
This came later when positions hardened on both sides - including the Western villification of Photios who, as Dvornik and others in the West attest, was reconciled to Rome and died in union with Rome while Rome affirmed the principle of the original Creed without the Filioque and Pope St Leo IV (love that saint!) produced tablets with the Nicene Creed in both Latin and Greek inscribed on them without the Filioque (or any other addition) and had them placed on the tomb of St Peter.
The Filioque is a specifically Latin expression which is rejected and will be rejected by the East as suggesting two Origins of the Spirit within the Holy Trinity.
For the East, it is a most clumsy theological expression at best. There is no doubt that Roman Catholic theologians can explain its meaning to mitigate the immediate alarms that sound in Eastern ears whenever they see it.
But then, the addition to the Creed just might have to be: “And the Son (see 17 page attachment with bibliography in appendix at end of missalette.”
The Filioque is a long-standing tradition in the West, it is deeply rooted in Latin Catholic liturgy and devotion and it is also popular in Eastern Catholic Churches as well.
Alex