Unfortunately I am dragged in to this discussion.
For the first time in the history of Indian Church Protestant faith entered through the British CMS missionaries. Indian Orthodox Church resisted the protestant movement started by a priest named Abraham who sided with missionaries. At that time the Orthodox church included the Jacobites also (i.e there was only one legal Malankara Metropolitan). Priest Abraham introduced a liturgy which was protestant in faith, i.e. removed the name of St. Mary and other saints, intercession, prayers for departed etc. Once this movement started, priest Abraham tried to get his nephew ordained. Indian Orthodox church refused ordination and excommunicated priest Abraham. Now Dn. Mathew (the nephew) was sent to Syrian Patriarch in Mardin to get ordained. Syrian Patriarch ordained him a metropolitan in the name Mar Athansius without consulting with the head of the Indian Orthodox Church. Had he consulted Indian orthodox church would not approve that ordination (it is happening even today - people going to Syrian Patriarch without the approval of the head of the Indian Church).
The ordination given to Dn. Mathew is the first ordination a Patriarch of Antioch gave to an Indian in the history fo Christianity in the world. He was instantly ordained priest, monk and Metropolitan by the Patriarch. (did the Patriarch think that he can gain control over the Indian church through this ordination? This is very much a possibility).
In 1843 he came back as Metropolitan and claimed that he is the legitimate Malankara Metropolitan (arguing that he is directly ordained by Patriarch). None of our bishops received ordination from patriarch before this incident.
So, the practise of Indian men going to Patriarch and getting ordained vioalting the Malankara Metropolitan is a tradition started by Protestants and continued by Jacobite faction. Mar Athansius seperated from the Church and formed the Protestant church.
Indian Orthodox church had a hard time fighting the Protestants, because they had the support of ruling Brits. There was one option, to invite the Patriarch himself (as he was the one who did it) and give him some more authority towards getting Brits to disapprove Mar Athanasius. Indian Orthodox Church won and got old churches and the theological Seminary back from protestant control (very similar to what is happening now after Jacobites legally seperated with a new consitution and registered as a new Church in India).
So, the Protestant movement would not have gained any importance in India if Patriarch consulted the head of Indian Orthodox church before giving ordination.
Peopl leaving the Church and going to Pentecostal etc. is not anything new. Neither was it due to present issues. To some extent the division between Orthodox and Jacobite sections of Malankara would have conributed to it.
But Indian Pentecostal movement was founded in 1924 by pastor K.E Abraham. Then came numerous other groups from the U.S. From that time they were converting people from all Orthodox, Roman Catholics and Mar Thoma churches.
So, I believe that Protestant church got a footing in Malankara due to the act of Patriarch not consulting with the head of Indian Orthodox church before giving ordination. Indian church had excommunicated this group, but Patriarch did not know this. Also, the Patriarch at that time had some connection with British authorities related to some issues in Syria.
Indian Orthodox church fathers always lead the Church in true faith and they did not enter in to any alliance with Protestant or even Roman Catholic. Even today it is only the Indian Orthodox church resisting Roman Catholic activities, while Jacobites are keeping smooth friendship with them and even communion.
So, it is a history of suffering we have and we believe that truth triumphs as H.H. Catholicos Gheevarghesee 11 said.
First thing is to remain humble and obey the head of Indian church infront of you and then honor unseen Patriarch serving the West. No one can serve two masters at the same time.
You asked me about what the Indian church did in 2000 years. Your existence in Christian faith is proof for that. If St. Thomas did not come to India and Indian fathers did not continue the mission you and me won't be knowing Christian faith.
It was H.H. Catholicos who encouraged Evangelism by approving the movement called 'Servants of the Cross' started by Metropolitan Mar Osthathios of Kandanad (I read in the biogrpahy of this great father that the Jacobites used to cast stones at him). The Bishop baptised about 20,000 through Servants of the Cross.
Here is one example of our mission: http://www.icbs.com/makodiya/
you can see H.H. Catholicos Mar Baselius Mathews 11 with metropolitan Mar Stephanos. H.H. is travels to any part of India, even at his age of 91 years to support our mission.
Please do not spread false stories about the Holy father of our Church.
So, people will leave, but more may join as directed by Almighty. Things are not in the control of you or me. If Almighty desires the Church will survive and withstand any difficulties.
Two years ago Coptic Bishop Mar Boulos visited our Indian Orthodox Church. Hope you know that H.G. Baulos is also doing evangelical work in Africa.