image from Catholic Voice
Eastern Christians fast from animal products and even wine and olive oil in some traditions during all of the four fasting periods of the year. Wednesdays and Fridays through the year are vegan as well. We might indulge in fish on Sundays. But do we really?
Roman Catholics barely fast at all, but if they fail at abstaining from meat on Fridays in Lent, they will go to Hell. But do they really?
In reality, Eastern Christians fast as well and as 'harshly' as they can and discuss their fasting plans with a spiritual father. The goal is 'more than last year and less than next year.' There is no 'letter of the law' because the ideal is no food at all.
Perhaps the reason why Roman Catholic fasting guidelines are so 'easy' is because there seems to be more of a philosophy of sticking to the letter of the law (even so- there are concessions made for age, health, etc)- the Church does not want to burden the people with sin, so the fasting/abstinence guidelines are very do-able for the majority of people.
So- the guidelines for fasting in the Eastern Christians churches are quite strict, but the personal responsibility to follow the ideal is potentially lax (when in conference with a spiritual father) and the guidelines for fasting/abstinence in the Roman church is quite relaxed while the personal responsibility is quite strict. Like so many parts of our faith, East and West are two sides of the same glass.
image from St Sofia Ukrainian Catholic Church