What you’ve said isn’t even close to historical fact.

Wales didn’t voluntarily join the union because it wasn’t an independent nation at the time. It was colonised by the English.

The Laws in Wales Acts 1535 and 1542 (Welsh: Y Deddfau Cyfreithiau yng Nghymru 1535 a 1542), also called the Acts of Union (Welsh: Y Deddfau Uno), were acts of the Parliament of England under King Henry VIII causing Wales to be incorporated into the realm of the Kingdom of England.

The legal system of England and the norms of English administration, including the use of the English language only, were applied to a mainly Welsh-speaking Wales. This created a single state and legal jurisdiction, which is now called England and Wales.

In 1284, with the Statute of Rhuddlan, England had annexed Wales, which was excluded from parliamentary representation in Westminster. Wales was divided between the Principality of Wales and many feudal territories called the marcher Lordships, which were effectively unified under the laws. The English system of county government was also extended across all of Wales.

https://en.wikipedia.org/wiki/Laws_in_Wales_Acts_1535_and_1542

As for Scotland, yes the parliament voted for it but there was much shenanigans afoot.

The Treaty details were agreed on 22 July 1706, and separate Acts of Union were then passed by the parliaments of England and Scotland to put the agreed Articles into effect. The Treaty of Union was eventually passed in the Parliament of Scotland. The first Parliament of Scotland was a unicameral Parliament that was first mentioned on record in the 13th century, when a meeting took place in Kirkliston in 1235. The Parliament met until “prorogued sine die” following months of intense debate, with 110 voting in favour for the treaty to 67 against. It is notable that 123 of the 300 members of Parliament were missing from one of the most controversial votes of the age. The passing of the vote has been described as a vote “to end Scotland’s independence”.[3]

After the negotiations ended on 22 July 1706, separate acts of parliament were drafted by both parliaments to implement the agreed Articles of Union. The Scots proponents of union believed that failure to agree to the Articles would result in the imposition of a union under less favourable terms, and English troops were stationed just south of the Scottish border and also in northern Ireland as an “encouragement”. Months of fierce debate in both capital cities and throughout both kingdoms followed. In Scotland, the debate on occasion dissolved into civil disorder, most notably involving the notorious “Edinburgh Mob”,[13] which threatened “Destruction to all the Promoters of the Union”.[14]

As the Parliament of Scotland was deliberating on 22 October 1706, the session had to be suspended “because the mob was threatening to break in”;[15] although this did not ultimately occur, they subsequently “attacked the house of Sir Patrick Johnston, a commissioner for union and former Lord Provost of Edinburgh.”[15] “Troops were brought into the city with orders to shoot if necessary, and several regiments were placed at Queensberry’s disposal on the Scottish border and in Ireland in the event of trouble.”[16] The prospect of a union of the kingdoms was deeply unpopular among the Scottish population at large, and talk of an uprising was widespread.[17] However, the treaty was signed and the documents were rushed south with a large military escort. Andrew Fletcher, a prominent Scottish patriot, argued that the ratification of the treaty would see Scotland “more like a conquered province”.[18]

https://en.wikipedia.org/wiki/Treaty_of_Union