Sure, that's a trade-off you have to make a decision on when designing the core architecture. If your users are sitting behind corporate T1 connections near an AWS data center bundle size doesn't matter at all. If your users are still on 3G phones it matters a ton. For somewhere in between it becomes a business decision: how much performance are you willing to trade for developer productivity?

You're comparison implies that T1 is faster than 3G, but that's probably not the case except in really poor coverage areas.

T1's maximum data transmission rate is 1.544 megabits per second. [0] While 3G's theoretical maximum is 21.6 Mbit/s for HSPA+. [1]

[0] https://en.wikipedia.org/wiki/T-carrier#Transmission_System_...

[1] https://en.wikipedia.org/wiki/3G#Data_rates

In practice, 3G is quite slower than that.