There is actually significant data to support the fact that pushing early academics before a child is ready and willing is more detrimental to their future academic success.
Many professionals agree, and studies have proven, that taking a "better late than early" approach is quite beneficial to the child. Allowing some learning to happen organically through play, hands on experiences, reading as a family, gives the little ones time to develop the best brains for learning in the future. Children who learn to read at 4 years old and children who are given the time and don’t learn until 8 years old all end up reading at the same level by 12 years old. And, very often, the late reader passes the early reader in reading level.
Comprehension is also a major component that most don't appreciate. There are studies that prove that by not waiting for the child to lead the way in learning to read, comprehension struggles pop up more frequently. Some of these same principles apply to math.
Early learning is best when the children are engaged and having fun! Here are some articles to support this train of thought:
Kindergartens Fail to Let Kids Play
Stanford researchers show we’re sending many children to school way too early
Let the Children Play, It’s Good for Them!
The decline of play in preschoolers — and the rise in sensory issues
Early Academic Training Produces Long-Term Harm
Report debunks ‘earlier is better’ academic instruction for young children