Basel IV and its impact on smaller banks' mortgage portfolios?

Been trying to get my head around the specifics of Basel IV, particularly how it's going to affect the capital requirements for mortgage exposures. It seems like the revised output floor and the shift in risk-weighting for residential real estate are pretty significant. For the larger, more diversified institutions, it might be an adjustment, but for smaller regional banks with a heavier concentration in mortgage lending, I'm wondering if this could really squeeze their ability to originate new loans or even force some portfolio restructuring. Are we expecting a noticeable impact on smaller lenders' profitability or their competitive position in the mortgage market once these rules are fully phased in? What's the general sentiment on how they'll adapt?