Come one, this is hardly anything to get worked up about.

A heavy boat is less fighty (as with a wide beam boat) ie when hit by the gust there is more resistance to heal.

A light boat is more resposive

A heavy boat takes a bit more effort to accelorate but once it has, it is easier to keep in the groove and does not stop as quick as a lighter boat. A light boat you can loose the groove very quickly if you stuff up.

You can stop an A very quickly if you hit a wave the wrong way. An F18 will push through it.

A heavier boat will forgive you if you gybe in strong winds without carrying good boat speed. A light boat you are swimming.

A heavier or wider beam boat is easier to sail then a light boat. That is not a negative for the lighter boats but fact.