Our creed has stemmed from Ebrahim Alaihi salaam who was completely clear when it came to his stance on beliefs which contradicted the one's of Allah.
"Indeed there has been an excellent example for you in Ibrahim and those with him, when they said to their people: “Verily, we are free from you and whatever you worship besides God, we have rejected you, and there has started between us and you, hostility and hatred forever, until you believe in God Alone.” [60:4].
Despite this being his own nation and his family as well he had the outstanding quality of hatred only for the sake of Allah.
He didn't say that he should maybe accommodatethese beliefs for his own "Maslihat" or to bring them with tact. He spoke out the truth clearly and Allah is commanding us to take cue from him.
A farmer once watched a rooster from afar, he felt jealousy burning in his heart due to the majestic feathers and crown of the rooster and felt annoyed at the roosters confidence.
He thus connived a plan to strip the rooster of all glory.
He therefore summoned the Rooster and with knife in hand commanded the rooster to stop crowing in the morning, the rooster felt to itself that crowing wasnt all that necessary, he could still be awake in the morning and perhaps chirp and that will be of benefit to his life.
He therefore from that day onwards began chirping.
A few days passed and he was summoned again, this time due to the brightness of his feathers, threatened once again with a knife hovering, the rooster felt that perhaps feathers wasn't the goal after all, it's the heart that counts.. Isn't it? He thus shaved off his feathers.
Few days later he was forced into clipping his talons.
Eventually the farmer summoned him and said"if you don't lay an egg you will die "
At this the rooster cried out, I should have rather died with honour, with my talons, feathers and voice than in this pitiful state!
Never will the Jews nor the Christians be pleased with you (O Muhammad صلى الله عليه وسلم) till you follow their religion. Say: ‘Verily, the Guidance of Allaah (i.e. Islamic Monotheism) that is the (only) Guidance.’ And if you (O Muhammad صلى الله عليه وسلم) were to follow their (Jews and Christians) desires after what you have received of Knowledge (i.e. the Qur’aan), then you would have against Allaah neither any Wali (protector or guardian) nor any helper”
[al-Baqarah 2:120]
The Quran has already made it a foregone conclusion that pleasing the disbelievers and compromise of Deen for them is a never ending path leading to Doom nonetheless.
The Deen is not ours to give discounts, therefore saying that it's better to practice on 50% Deen than losing everything is not our call to make, we are not accountable if we are forced, what we are accountable for however, is compromising willfully.
When free mixing of religions take place instead of becoming an aid to ISLAM we actually promote perreneliasm instead of Islam, what we are presenting is not Islam, it only has the name as the hadith had predicted that nothing would remain of Islam besides its name.
Dying protecting true Islam is much better than living with a mock Islam
That is why Abu Bakr Radiallahu anhu said "even if a rope that was given in the time of Nabi Sallalaaahu alaihi wasallam is not given today in zakah I will wage war against such individuals, shall deficiency come to Deen while I'm alive??"
We should therefore never fall for these arguments, it is mostly fame and the corruption of the heart as well as the foundation of Allah himself alone being the protector of the believers being wanting that leads shallow individuals to tread down this slippery path of deviation.
Attending funerals, festivals, marches, prayers and lectures with interfaith all pushes the same agenda and are all strictly prohibited in Islam.
May Allah guide us and protect us.