Hi,

If you are looking to remove the kanban view of the customers , what you can do is that, you can define a new action for the menu or you can change the original action of the menu.

Giving new action for the menu:

<record id="action_partner_form_no_kanban" model="ir.actions.act_window">
    <field name="name">Customers</field>
    <field name="type">ir.actions.act_window</field>
    <field name="res_model">res.partner</field>
    <field name="view_type">form</field>
    <field name="view_mode">tree,form</field>
    <field name="context">{}</field>
</record>

<menuitem id="sales_team.menu_partner_form" parent="sales_team.menu_sales" action="action_partner_form_no_kanban" 
          sequence="3"/>

Changing the original action of the menu,

<record id="base.action_partner_form" model="ir.actions.act_window">
    <field name="name">Customers</field>
    <field name="type">ir.actions.act_window</field>
    <field name="res_model">res.partner</field>
    <field name="view_type">form</field>
    <field name="view_mode">tree,form</field>
    <field name="context">{"search_default_customer":1}</field>
    <field name="search_view_id" ref="view_res_partner_filter"/>
    <field name="help" type="html">
      <p class="oe_view_nocontent_create">
        Click to add a contact in your address book.
      </p><p>
        Odoo helps you easily track all activities related to
        a customer: discussions, history of business opportunities,
        documents, etc.
      </p>
    </field>
</record>

First method is the better way, it will only remove the kanban from sales-> customers menu. If you do the second means, the kanban from all the customers view will be removed.

Thanks