There will be houses you can afford without Help to Buy, and taking the long view, these will be better value.
If you use Help to Buy, you need to appreciate that over time, you will pay more. There will be costs involved in re-mortgaging and legal fees, plus the intitial orice you pay is inflated. Yes, it means that you can have that particular house today and the mo they payments will be affordable for you, but overall you will spend significantly more.
The question is whether you are willing to do that. Some people are prepared to do that when the hey could afford a non-help to buy house and avoid those extra costs. Why? Because they are more interested in having the thing they want today soon and are willing (or don't really think about) th pay significantly more overall because on a monthly basis is is affordable and they either aren't worried about overall cost or struggle to compute the overall costs because they are long term and so feel less real. Some people also will do this because they really like new builds and either don't like the idea of there being a chance of needing to do work on an older house, or lack the funds to feel confident they could pay for such works. Often this system appeals to people who have only a small deposit and/or who know that they will never have a big chunk of savings behind them to fund bigger expenses, so prefer to have a clearly set mo they outgoing that they know they can afford, even if it means paying more overall, to avoid surprise big payments that they mig struggle with.
I think there is a place for Help to Buy when it enables someone to move from rented to homeownership when otherwise they could not afford anything even after saving for a good while. However, I think lots of people go into Help to Buy who could avoid it and avoid the significant extra costs that come with it. Lots of people could either save for a few months more to boost their deposit to a size large enough not to need help to buy, or look at other non newbuild properties that might be cheaper and they could afford without help to buy. I think it's a shame that lots of people get drawn j to the scheme and perhaps are tempted by a bigger house (and much bigger cost overall) than they really need or can afford over the long term. They often realise the impact of their choice a few years in, but are blinded at the time by the offer of a bigger, new house and affordable monthly starting payments.
So definitely take the long view and make sure you request written details of all the costs involved up first of help to buy along with costs you would incur at later points by remaining in the scheme (interest after 5 years) or by re-mortgaging and do calculations for a variety of different house prices in 5 or 10 years, bearing in mind new builds often decline in value for a couple of years and also we are heading into recession and lots of job losses.
If you can move and avoid it, I'd work pretty hard to avoid it personally. However, clearly lots of people choose this each year and it seems to work for them, but go into it with your eyes wide open.