The Green party of England and Wales has announced Sarah Wakefield as its candidate for the upcoming Makerfield byelection. The constituency is split between Greater Manchester and Wigan, and the latter’s council saw a surge in support for Reform in the latest local elections, with the party taking 24 of the 25 seats up for grabs.

The showdown between Labour’s Andy Burnham, the Greens, Conservatives and Reform UK will be seen as a test case for how Labour would fare under Burnham as leader against the national threat of Reform UK in the next election. It is within this context that there has been internal discussion in the Green party about it stepping aside in the seat so that it does not split the progressive vote and, in so doing, allow Reform to win the seat. “A vote for the Greens in Makerfield is a vote for Reform” is a common slogan being shared by Labour party members.

At the weekend, senior Green figures, activists and academics released a statement urging the party to run a scaled-back campaign in return for the promise of electoral reform at some point in the future. The former party leader Caroline Lucas has also called for the Greens to step aside on the same grounds.

The calls weren’t just from Green politicians, though. The Labour MP Rupa Huq added her voice to the fray by claiming that, in 2017, the Greens stepped aside to allow her a clear run at her seat in Ealing Central and Acton. Back in the pivotal Gorton and Denton byelection in February, Labour’s deputy leader, Lucy Powell, published public letters urging the Greens to step aside, claiming their presence would “let Reform in by the back door”. The Greens’ Hannah Spencer ended up winning convincingly, with the Labour party pushed into third place behind Reform.

The thing with these calls to step aside is that they misunderstand the new role and position of the Green party in British politics, their relationship to the Labour party and the battle against rightwing populism.

Last year, the election of Zack Polanski as leader of the Greens put the party on a stratospheric trajectory. Vastly improved communication of ambitious and radical Green party policy coincided with the collapse of Starmerism. The surge in support – with the Greens now the second most popular party, according to a YouGov poll – has respositioned the party from being an electoral pressure group to a genuine force in British politics. This is precisely because it shows ambition and hope wherever it is, and no matter how unwinnable the battle seems.

Many voters see it as a vehicle for genuine change. Much has been made of Burnham’s progressive politics, but in the short space of this campaign, he has already backtracked on several points. According to allies, he has already backed the home secretary, Shabana Mahmood’s, controversial and hardline immigration policies, has stated that he’ll retain Rachel Reeves’s fiscal rules that have so hampered ambition and investment, and changed his views on transgender rights. It would be naive to argue that Burnham will commit to progressive change without the pressure exerted by Green candidates running against him.

More broadly, the explosion of support for the Greens – and the Labour party’s reaction to it – has exposed a quirk of modern British politics. Namely, that there are many within Labour who believe the Greens to be an extension of their party – a faction on the left, filled with annoying people who they criticise for being unrealistic, but then ask to fall into line during critical moments so the sensible adults can be elected. It is a symptom of the way the left is treated across politics – as illegitimate political actors. But, the fact is, the Greens earned their place at the table at May’s local elections, when Labour lost four seats to the Greens for every one lost to Reform.

There has also been no reckoning with the fact that Labour is in part responsible for the popularity of Reform, whose base is made up of disaffected and disenfranchised voters left behind by the two main parties. Nigel Farage has exploited these frustrations by pushing anti-immigration wedge narratives (that have been simply accepted by Labour) and capitalising on the chaos. The difficult truth is that a vote for Labour is a vote to continue spreading the discontent upon which Farage feeds.

What’s more, if the Greens were to get into line behind Labour, it would give Reform ammunition to continue to pitch themselves as outsiders and representatives of the people, despite being predominantly made up of wealthy individuals and ex-Conservatives.

It is understandable, and completely reasonable, to be terrified of what a Reform government might look like. On that basis, I fully understand those urging the Greens not to stand. But the truth is that supporting the status quo won’t beat rightwing populism. History tells us that only by standing up and offering a genuine alternative will the fight be won.

• Ben Smoke is a freelance journalist