Seems good for negotiation. If a company offers you $180k, (given that range) they're implying you're in the lowest 10% of your field. Ask why they're willing to hire you if you're so terrible. If you're in the top 25%, you should be worth $700k.
It's very possible that lots of people have $90k stills and only an extremely tiny handful have $700k skills.
After all that's how it is in the general population: Most people are $10/hour plumbers in terms of skills. Only a few people (we happen to mostly call them plumbers) are worth $200/hour or more.
The same is true of software.
When I go through candidates for an open position, I find very little correlation between experience and salary demands. Propensity for audacity seems to have more to do with it.
It would count as a red flag for the senior and negatively impact hiring.
Negotiation is typically lopsided in favor of the employer. With a range like that, they've handed you a piece of information that tilts the balance in favor of the candidate. Even better if it's a lie, it still works in your favor. Use that nugget of information to your advantage.