Here's some more specific information about the differences between Boost 148 and Boost 141:
Boost 141
Boost 141 is an older standard that was commonly used on mountain bikes prior to the introduction of Boost spacing.
The spacing between the dropouts on a non-Boost hub is 141mm, which is 6mm narrower than the spacing on a Boost hub.
Non-Boost hubs have narrower hub flanges, which can create a weaker and less stiff wheel compared to a Boost hub.
Non-Boost hubs have a narrower spoke bracing angle, which can decrease the lateral stiffness of the wheel.
Non-Boost spacing allows for a narrower chainline, which can be advantageous for certain drivetrain configurations.
Non-Boost spacing is still used on some mountain bikes, particularly on lower-end models that are designed to be more budget-friendly.
Boost 148
Boost 148 is also known as Boost spacing and is a newer standard that was introduced in 2015.
The spacing between the dropouts on a Boost hub is 148mm, which is 6mm wider than the spacing on a non-Boost hub.
The wider spacing allows for wider hub flanges, which creates a stronger and stiffer wheel.
The wider hub flanges also allow for a wider spoke bracing angle, which increases the lateral stiffness of the wheel.
Boost spacing also allows for a wider chainline, which improves shifting and chain retention.
Boost spacing has become the standard for most modern mountain bikes, and most new wheels and hubs are designed to fit this standard.