In a simple linear regression model $Y_i = \beta_0 + \beta_1 X_i + \epsilon_i$, suppose the error variance is heteroscedastic, specifically $Var(\epsilon_i) = \sigma^2 X_i^2$. If we use Ordinary Least Squares (OLS) to estimate $\beta_1$, which of the following is true regarding the estimator $\hat{\beta}_1$?