Brief history of landlord and tenant
Historically most "tenancies" have been defined by long-term obligations.
Indeed one of the defining features of serfdom is that the serf cannot be alienated from the land. The overlord can be slain and replaced in wars and conquests, but the peasantry who actually operate the land to produce crops cannot be lawfully dispossessed from it so long as they are performing their customary obligations.
The nature of those customary obligations are such that a peasant family have wide latitude to fulfil them (in other words, it is not dependent on the competence or capability of only a single individual), and they are not so onerous to meet in ordinary times. In times of catastrophe, the lord would be expected to provide forbearance or relief.
In the event of a persistent and wilful failure to meet customary obligations, there could ultimately be dispossession for the serf, but there was large latitude to manage the situation before it reached the point of actual dispossession of the entire serf family.
The serf who is considered appurtenant to a agricultural landholding, is to be contrasted with the slave who is considered personal property of a master.
The laws in England and Wales governing landlord and tenant predate the industrial revolution. Slavery has been repugnant to the common law since time immemorial.
Under these historical circumstances, a landlord almost never has any right to possess the land itself - only to extract customary rents.
Market reforms
There has been a tendency since the industrial revolution for land to change hands more frequently and for tenancies to be auctioned to the market more frequently.
The time since the industrial revolution has also essentially been characterised by increased violence towards people, sanctified by movements in market prices and the rights to enforce market demands against those who have little or no capability of meeting those demands. Such enforcement occurs by starving people or throwing people out of shelter onto the streets.
It's primarily under these circumstances of market violence that questions arise like "what do you do to someone who won't or can't pay the market rent?".
There have also been ups and downs, legally, in the balance of rights and obligations between landlords and tenants over the years and centuries. There has also been a shift from people holding primarily agricultural tenures in rural areas, to holding primarily residential tenures in urban areas.
Circumstances today
The post-war period that preceded the current era, was characterised both by increasing security and stability of tenure, and by various measured to increase the supply of housing to control the scarcity which the market creates when left to itself.
Today however, we are at a similar nadir of protection for residential tenants as in the Victorian period, and a similar merry-go-round of short tenancies and evictions of the poor which exists as a kind of violence sanctioned by market verdicts.
It's under these circumstances of violence that landlords are constantly considering how to enforce rack-rents, or enforce evictions on those who can't or won't pay those rents.
By historical standards, it is already quicker and easier to terminate a tenancy than at most times in history. So they are not particularly "weighty" or "sacred" today.
Illegal dispossession
There is still a basic modicum of protection for the occupier of land, and this dates back to legal time immemorial, which is that those in current established possession are assumed by the law to have the right of possession.
The main evil with which the law has always been concerned, as far as possession is concerned, is over property disputes erupting into violence, and of gangster groups forming to enforce changes in possession against the will of the occupier (whether with legal rights or not, and whether at the behest of the landlord or merely another would-be tenant).
The solution to this has been to protect the right of established possession, and to redirect all other disputes into the courts.
The emphasis here is less about mutuality or consent, but of allowing enough time for a justice process to take place, and limiting the immediacy of any violent eviction (which can as easily provoke strong emotions in the tenant, and harm the landlord wanting possession as much as the tenant who has possession).
