What fallacy is it to dismiss something by comparing it to something similiar?

To address the argument in the given tweet by focusing on any logical fallacies, cognitive biases, poor logic, or poor reasoning, and to answer the specific question posed, here's a breakdown:

When a person dismisses something by comparing it to another similar thing, this often falls under the **False Equivalence** fallacy. This fallacy occurs when an argument incorrectly portrays two situations as similar, when they are not equivalently comparable in a meaningful or relevant context.

**Explanation and Examples**:

1. **False Equivalence**:
- **Fallacy Description**: False equivalence happens when it is assumed that because two things share one characteristic in common, they are equivalent in other respects.
- **Example**: Saying that "Smoking and eating candy are both bad for your health, so they must both be equally bad," fails to consider the vast differences in the degree and nature of harm caused by smoking as compared to eating candy.

2. **Other Potentially Related Fallacies**:
- **Strawman Fallacy**: Sometimes, while engaging in false equivalences, a person might misrepresent the original argument to make it easier to attack the comparison.
- **Red Herring**: In comparisons intended to dismiss an argument, the person might divert attention away from the core issue.

**Assessment of Logical Reasoning**:
- Arguments based purely on dismissive comparisons often miss the nuances and complexities involved in the issues.
- Relying on such comparisons without addressing the unique elements and context-specific factors leads to poor logic and reasoning.

Returning to your specific context—the tweet dismissing a group by comparing it to a similar group could indicate a failure to recognize the different underlying factors or contexts that differentiate the two groups, making it a case of false equivalence.

To conclude, the fallacy of dismissing something by comparing it to something similar is typically the **False Equivalence** fallacy, which assumes unjustifiable equality between two scenarios, aspects, or entities.