Reproduction:
-- Note: Type of NumberValue.Value is 'double', not 'float'
local TweenService = game:GetService("TweenService")
TweenService:Create(Instance.new("NumberValue"), TweenInfo.new(), {Value = 10})
--> TweenService:Create property named 'Value' on object 'Value' is not a data type that can be tweened
Expectation: Doubles, while not appearing often as property types, should still be tweenable.
Aside: Value classes (NumberValue, IntValue, StringValue, etc) are misreported as “Value”.