Odoo uses the same stock.production.lot object for Lot and Serial Number. In case of serial number, it is normal that this serial number is located in one location at a time, but in the case of Lot inventory, it can be divided into different locations, and it is not possible to display multiple locations in a single field, that's why Odoo added a smart button (Location) in the Header section of form view. If the user clicks on the Location Smart button, he will know where the inventory is.
If you want to show all locations on the list/tree you need to create a custom field (many2many) which calculates the field it will check where the serial/lot number is stored and add those locations.
You can refer to the following code snippet
location_ids = fields.Many2many('stock.location', compute='_compute_locations', string="Location")
def _compute_locations(self):
for lot in self:
location_ids = self.env['stock.quant'].search([('lot_id', '=', lot.id), ('quantity', '>', 0), ('location_id.usage', '=', 'internal')]).mapped('location_id').ids
lot.location_ids = [(6, 0, location_ids)]