This clause is negotiable however most landlords will not remove this from the lease as they don’t want tenants removing everything upon move out and damaging the walls or floors. They also don’t want to be left with a bunch of random improvements that they have to remove to prepare the space for the next tenant.
If a landlord delivers you the retail space in white box condition then they will typically want it returned that way when you move out.
Do everything you can to have this clause removed. For more info on this check out this post: https://www.austintenantadvisors.com/blog/retail-space-leasehold-improvements-alterations-fixtures/