Is the Sony A7 IV better than the Tamron 28-75mm f/2.8 Di III VXD G2?
It depends on what you shoot. Sony A7 IV scores 4.7/5 in our review, while the Tamron 28-75mm f/2.8 Di III VXD G2 scores 4.6/5. See the spec table and use-case breakdown above for our verdict.
Which is cheaper, the Sony A7 IV or the Tamron 28-75mm f/2.8 Di III VXD G2?
Sony A7 IV sells around $2499, and Tamron 28-75mm f/2.8 Di III VXD G2 around $899. The Tamron 28-75mm f/2.8 Di III VXD G2 is the cheaper of the two.
Which one is better for beginners?
Both are capable, but beginners usually do better with whichever has the simpler interface and more forgiving autofocus. Read the "Winner by use case" section above for our specific call.
Should I upgrade from the Sony A7 IV to the Tamron 28-75mm f/2.8 Di III VXD G2?
Only if the gap in features you actually use is wide. If you already own one, the marginal upgrade is rarely worth the cost unless a specific shortcoming is blocking your work.