Mypy allows to compare NewTypes created from Decimal

Bug Report

Mypy does not produce an error when comparing NewTypes based on Decimal.

To Reproduce

from decimal import Decimal
from typing import NewType

# Comparing Decimal NewTypes is OK 
FirstDecimal = NewType("FirstDecimal", Decimal)
SecondDecimal = NewType("SecondDecimal", Decimal)

FirstDecimal(Decimal("0.1")) == SecondDecimal(Decimal("0.1"))  # ! mypy ok

# But comparing other NewTypes is not
FirstInt = NewType("FirstInt", int)
SecondInt = NewType("SecondInt", int)

FirstInt(1) == SecondInt(3)  # mypy error

FirstString = NewType("FirstString", str)
SecondString = NewType("SecondString", str)

FirstString("bam") == SecondString("boo")  # mypy error

Expected Behavior

Mypy produces Non-overlapping equality check for all three comparisons.

Actual Behavior

Mypy produces Non-overlapping equality check only for int and str NewTypes.

Your Environment

• Mypy version used: 1.1.1
• Mypy command-line flags: --strict
• Mypy configuration options from mypy.ini (and other config files):

[tool.mypy]
strict = true
show_error_context = true
show_error_codes = true

• Python version used: 3.10.8

Start by running the minimal Python reproduction with mypy 1.1.1 and --strict, comparing the Decimal-based NewTypes with the int and str cases. Trace the type-checking path for non-overlapping equality checks; the issue is done when equivalent NewTypes consistently produce the expected diagnostic and regression coverage confirms all three comparisons.