Thanks. I did not indend to suggest you are wrong. I am just trying to understand why "become" is used by some authors despite the fact that is seems to sound odd to you.
Here are some examples (all authors are native-speakers):
a. became neglected
"In this Hurly-burly stood the Roman Empire after the Death of Confiantine, wherein Civil and Military Discipline became neglected, till the Reign of Julian the Apostate"
"when many crimes received no visible punishment, the divine commands became neglected, the powerful oppressed the weak and the poor, and there was a general prevalence of levity"
"That knowledge of God which was at first bestowed upon Adam, and continued to a great extent even after the veil of a carnal nature was drawn between him and his Creator, soon became neglected, and, consequently, corrupted"
"and this law, through the lenity of the duke, being utterly disregarded, the holy institution of marriage became neglected"
"whereon the service of the altar became neglected, and the priests despising"
Es fällt aber auf, dass die meisten Belegstellen aus dem 18. Jahrundert oder frühen 19. Jahrhundert stammen.
In einigen der Belegstellen wird "become neglected" auch i.S. von "verwahrlosen" verwendet. Auch dict.cc kennt diese Bedeutung:
to become neglected verwahrlosen [Gegend, Park etc.]
b. became superseded
"SPA became superseded by single X-ray absorptiometry"
"The 13th century was not completed before the simple style of Salisbury Cathedral became superseded by one of richer character. Westminster Abbey is perhaps the earliest example on a large scale"
"he need to debate the purposes of the curriculum and to seek a rationale for the inclusion of each subject became superseded by the simple need to fulfil government policy"
"until at last, even the relicks of popular privilege became superseded by military force"
"Eventually, this use of timber construction became superseded by the advancing ability of the artisans (stonemasons) by developing a form that was more applicable to this new material"
"Every consideration, except what had a tendency to promote these great objects, became superseded—Salus populi supremo, lex, prima lex, media lex."
"It became superseded in the 1930s by a language that was influenced by an anthropology emphasizing cultural rather than racial differences - themes which will be discussed more fully in susbequent chapters on R. F. A. Hoernle and Edgar ..."
"That in a question which concerned the welfare of the people, every consideration, except what had a tendency to promote that great object, became superseded"