Doesn't "no longer" indicate a contrast between what is present and what is past? Hence, there is no need to provide a time reference. Or is it necessary to establish a past time frame in the same sentence?
Yes, Essam Nasr, it does, but, unlike "used to," "would" requires a time adverbial. In this old thread, we can read:
From LG Alexander Longman:
quote:
'Would' can be used in place of 'used to,' but, like the simple past, it always requires a time reference. We often use it to talk about regular activities, particularly in narrative, or when we are reminiscing.
Surfing the Internet, I found a similar explanation in a book entitled "Active Grammar Level 3" by Mark Lloyd and Jeremy Day (Cambridge University Press):

Additionally, I found a comment here:
With ‘would’, a time reference is usually given, whereas with 'used to' it is not. Consider the following:
A: Do you go to the gym?
B: No, I used to go, but not anymore.
It doesn’t seem natural in any way to use ‘would’ instead of ‘used to’ here.