There has to be WELL FOUNDED fear of persecution and harm. Just wanting a better living standard is not sufficient.
Who is a refugee?
A refugee is a person who has fled their own country because they are at risk of
serious human rights violations and persecution there. The risks to their safety and life were so great that they felt they had no choice but to leave and seek safety outside their country because their own government cannot or will not protect them from those dangers. Refugees have a right to international protection.
Who is an asylum-seeker?
An asylum-seeker is a person who has left their country and is seeking protection from
persecution and serious human rights violations in another country, but who hasn’t yet been legally recognized as a refugee and is waiting to receive a decision on their asylum claim. Seeking asylum is a human right. This means everyone should be allowed to enter
another country to seek asylum.
https://www.amnesty.org/en/what-we-do/refugees-asylum-seekers-and-migrants/Another country = one other country, not many other countries. The people crossing Ghe Channel are not fleeing France. Mexicans crossing into the US are nor fleeing persecution and human rights violations. Others from outside Mexico should claim asylum in another country nearest to their own and seek asylum there and then if accepted as refugees, seek resettlement from a country that wants to resettle them. Almost none of the boat arrivals from Indonesia were Indonesians, except the boat crew.
With international travel no incomparable cheaper and easier now than when the Refugee Convention was drafted, large number of people from a large number of poor countries embark on country shopping with bogus claims of serious human rights violations and fake claims of persecution.