The meaning of the poem as a whole is pretty clear. (We will come back to the unusual wording in a minute, though).
The speaker is about to visit an old people's home. On the way, he thinks about the various residents. They suffer from varying degrees of decrepitude. Some can get themselves dressed, read books and play music. They are the "elite". The "average majority" aren't really able to do much more than sit in front of the TV and participate half-heartedly in singalongs that they don't really enjoy. The worst of all are so decrepit and senile that they are scarcely distinguishable from plants.
All, however, are united by the fact that they are no longer wanted by their families. When they were less old, their grandchildren loved them, but they don't visit any more. The poem concludes by asking whether it is wrong to pray that death, for the person he is visiting, should be quick.
WHAT MAKES THIS POEM SPECIAL
This poem is not about particular inhabitants of a particular old people's home. It is actually about our own mortality. A poem that said "Isn't it scary that we will all grow old and, one day, die" would not be a terrible remarkable piece of verse. By very skilled use of structure and style, this poem invites us to meditate on this difficult subject.
The first thing that leaps out is the formality, stiltedness and often incongruity of the language used. I am not sure that the word "limitory", in the first line, even exists. "Decent" in the second line is used as a verb (as in "to make oneself decent") whereas most of us would recognise it as an adjective. "Glum" is used as a noun (a "glum beyond tears") whereas we would normally use it as an adjective. These oddities of language appear early in the poem and operate to distance us from the inhabitants of the old people's home. They also echo the tendency of the senile to make mistakes in their speech.
So, in the first part of the poem, the inhabitants of the old people's home are largely objectified. They are not described as human beings, so much as categorised by what they can do. However, in the midst of the extended first section, hints of humanity peek through. There is some suggestion that the "elite" might be unhappy because they are actually conscious of their surroundings. The average majority are said to "endure" TV which again hints that these people might actually have the ability to experience pleasure (and indeed are not experiencing it). But largely, the first part of the poem is describing the residents, rather than empathising with them. It is also written in the present tense: describing what the residents are like at the moment.
Then the tone changes. These people haven't always been in the old people's home. They have previously been members of a family. Grandchildren loved them, but now they are "stowed out of conscience" like unpopular luggage. At this point in the poem, the residents have become human, but the description is still about them and their feelings. Also, this part of the poem invites us to experience sorrow for the loss of their pasts. It is essentially retrospective in tone.
Right at the end of the poem, we realise that the writer is speaking on his way to visit a long-standing friend. He is now thinking about the future: ostensibly what will confront him when he gets to meet his friend. That part of the poem introduces us to someone else's perspective. And that is when our brains really get working. If the writer knew his friend when she was young and beautiful, it is reasonable to assume that he is not too dissimilar in age to her. When he thinks about the future, he must be worrying about what his own old age will be like. The future tense of the last aspect of the poem, and the abrupt change of perspective, causes us to reflect on our own mortality.
What, then, do we think about the rhetorical question at the end? Is he wrong to pray for a quick death for his friend, or is life too precious for that? I have the suspicion that the contrast between points of view, and tenses is deliberate. Perhaps the suggested answer is that onlookers might think that they are being merciful in praying for a swift death for the residents of the old people's home, but the residents themselves are doing no such thing and are clinging to life almost instinctively. Perhaps also the poem suggests that your answer to the question might change over time. When you are young and healthy, you might think that death is preferable to decrepitude, but as you get older you change your mind.
What is clear, though, is that the poem achieves a large part of its appeal not from a particularly complex thought, but rather from a very skilled structure that alternates perspectives and tenses to invite a complicated reaction to the rhetorical question at the end.