They should be allowed in mainstream schools so that they know what it's like around other children, And other children learn how to act around people with learning disabilities and become more tolerant. However, There should (in most cases) be a support teacher who basically helps to look after them.
The child with disabilities needs to know what it's like around children without disabilities. School is there to teach you how to be ready for the real world, And the real world is mostly made up of adults without disabilities. It also benefits the other children because if they never met people with disabilities as a child they'll have no idea how to handle it as adults.
Depending on context and where you come from, "learning disabilities" may mean specific learning disabilities or general learning disabilities (i. E. Intellectual disabilities). Some mainstream schools have additional support and/or special education classes for students with disabilities.
In my opinion, Students with disabilities that impact learning should definitely be accepted into mainstream schools as long as the safety of all parties can be ensured, The student concerned is able to learn and the learning of other students is not majorly disrupted because of the student's needs.
It is a sad reality that bullying does exist at schools (which may come from other students as well as staff) and some students with disabilities may be particularly vulnerable; however, Personally I do not believe the solution to that is necessarily to take students with disabilities who are being bullied out of mainstream or altogether avoid putting vulnerable students in mainstream. It DOES mean, However, That we must be discerning and aware that bullying is an issue in some schools, And try to do what we can to lessen bullying in schools.
If the nature and severity of a student's disability means that they are virtually unable to benefit from a mainstream class or school setting and/or there are no mainstream schools nearby with appropriate support, Or if there are health and safety risks, Then perhaps an alternative school setting may be appropriate; however, In many cases, I don't believe mainstream schools have the legal right to refuse children with learning disabilities (that can be accommodated) entry anyway.