WordPress powers nearly half of the websites in the world. It is popular for good reasons, but that does not mean it is right for you. Here is an honest comparison, including when WordPress is the better call.
WordPress is a content manager: you install themes and plugins, and the site is assembled from prefabricated parts.
Next.js is a development framework: the site is built to measure, without loading code you do not need.
The analogy I use with clients: WordPress is a prefab house (fast to assemble, limited to what it ships with); Next.js is a house built by an architect (exactly what you need, no waste).
The difference here is large. A typical WordPress site with a commercial theme and 15 plugins loads in 3 to 6 seconds. A well built Next.js site loads in under 1.5 seconds.
Why does it matter? Google uses speed as a ranking factor, and the studies are consistent: for every extra second of load time, a meaningful share of visitors leaves. If your site takes 5 seconds, many people leave before they ever see what you offer.
WordPress is the most attacked platform in the world, precisely because it is the most used. Most hacks are not against WordPress itself, but against outdated plugins.
A Next.js site does not have that attack surface: there are no third party plugins running on your server.
WordPress is usually cheaper upfront. Next.js usually costs more at the start but less over time (no premium plugin licenses, no mandatory monthly maintenance).
If your site is mainly a blog with heavy daily publishing, WordPress makes sense.
For almost everything else (local businesses, service companies, stores, applications), Next.js delivers a noticeably better result in speed, security, and search rankings.
The important part: do not choose the technology first. Define what your business needs, and let the tool follow from that.
Tell me what you need and I will get back to you with a clear plan and a real estimate.