Indeed, it'd be outright foolish of me to assert otherwise, especially given what
@Typhoon detailed in the following reply. The way the villagers here were treated isn't just scandalous, it was/is flat-out disgusting. And given how it's another example of England shafting Wales for the former's own benefit, I'm not in the least bit surprised that resentment lingers to the degree it does.
One of the reasons this has become
quite the rallying call for the Welsh Nationalists is that it wasn't just a community which was destroyed, it was specifically a Welsh-speaking community. Welsh had been actively suppressed since at least the 19th century, with its use for official purposes being outlawed and famously,
children punished for being heard to use the language at school, even in to the 20th century.
Events such as the clearance of Capel Celyn were partly responsible for the rise of Welsh Nationalism and gave rise to the famous speech by Saunders Lewis,
Tynged yr Iaith which is widely regarded as the starting point for a lot of direct action and the fact that Wales now has a
parallel state-funded education system (mostly) which offers education entirely through the medium of the Welsh Language if desired. Even Margaret Thatcher gave in to the Nationalists, allowing the creation of the
Welsh-language television station S4C which had its opening night the day before Channel 4 in the rest of the UK.
As we seem to be allowing forced clearances rather than simply settlements which have "petered out", other Welsh clearances include the community in the
Epynt Mountiain to create the Sennybridge training camp, the removal of the village of Llanddwyn to create
Llyn Vyrnwy and the clearance of the community in the
Elan Valley for yet more reservoirs. It's not unusual to have to clear settlements for this sort of purpose, but the manner in which it is done can make a lot of difference and, of course,
not all of them were done purely for the benefit of the Saeson!
(most links to Wikipedia, by the way; full disclosure, Cornish-Welsh heritage, educated in Welsh by some rather politically active teachers <ahem> years ago)